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Comprehensive Guide to EKG and Monitoring Devices

3

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R

rylee helmholtz

11/16/2025

Physics

EKG and Monitoring Devices

61

Nov 16, 2025

9 pages

Comprehensive Guide to EKG and Monitoring Devices

R

rylee helmholtz

@ryleehelmholtz_cfgo

Cardiac electrophysiology explores how the heart's electrical system works to... Show more

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What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Cardiac Cells and Their Properties

Ever wondered what makes your heart beat without you having to think about it? It's all about cardiac electrophysiology (EP), which examines your heart's electrical activity through specialized tests.

Your heart contains two main types of cells. Myocardial cells are the working cells responsible for contraction, while pacemaker cells are specialized cells that form electrical impulses spontaneously and control the heart's rhythm.

Cardiac cells have four key properties. Automaticity is the ability of pacemaker cells to create electrical impulses without outside stimulation. Excitability allows cardiac muscle cells to respond to stimuli, while conductivity enables them to receive and pass electrical signals to neighboring cells. Finally, contractility is their ability to shorten, creating the muscle contractions that pump blood.

💡 Did You Know? Over 200,000 catheter ablation procedures (a treatment for heart rhythm problems) were performed in Europe in 2013 alone, showing how important understanding cardiac electricity has become!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Cardiac Action Potential and Electrical Phases

The heart's electrical activity creates a measurable signal called the cardiac action potential. This energy moves electrolytes across cell membranes, creating current flow that appears as waveforms on an ECG.

The electrical cycle has three main phases. Polarization is the resting state, depolarization occurs during stimulation, and repolarization is when the cell returns to resting. On an ECG, you'll see these as distinct waves: the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the ST segment and T wave (ventricular repolarization).

After being stimulated, cardiac cells need recovery time called refractoriness. The Effective Refractory Period (ERP) is when cells absolutely cannot respond to stimulation. The Relative Refractory Period (RRP) follows, when cells might respond, but only to stronger-than-normal stimuli.

🔍 Key Insight: The configuration of the cardiac action potential varies depending on cell location and function. Fast response action potentials occur in atrial and ventricular working myocardial cells and His-Purkinje fibers.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

ECG Basics and Electrodes

An ECG provides valuable information about your heart's electrical activity. It can show the orientation of your heart in your chest, identify conduction problems, assess muscle mass, detect damage from lack of oxygen, and reveal how medications and electrolytes affect your heart electrically.

However, an ECG has limitations. It doesn't directly show the mechanical condition of your heart muscle - that requires checking pulse and blood pressure.

To record an ECG, electrodes are placed at specific locations on your chest. These connect to an ECG machine via cables that conduct current. The resulting leads record the electrical activity as voltage differences, allowing doctors to view your heart's electrical activity from different angles.

Remember This: While ECGs show electrical activity, they don't show mechanical function. Your heart might be electrically active but not pumping effectively!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

ECG Leads and What They Show

ECG leads work like different cameras capturing your heart's electrical activity from various angles. Standard limb leads (I, II, III) form Einthoven's triangle, with the right arm electrode always negative and left leg electrode always positive.

Lead I records between left arm (+) and right arm (-), viewing the lateral wall of your left ventricle. Lead II records between left leg (+) and right arm (-), showing the inferior surface. Lead III records between left leg (+) and left arm (-), also viewing the inferior surface.

The augmented limb leads (aVR, aVL, aVF) provide additional perspectives. aVL views from the left arm toward the lateral wall, aVR from the right shoulder (usually showing negative waveforms), and aVF from the left foot/leg toward the inferior surface.

📝 Quick Tip: Think of leads as different camera angles around your heart. Each lead captures a unique view, helping doctors spot problems that might only be visible from certain directions.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Ambulatory ECG Monitoring

Ambulatory electrocardiographic monitoring (AECG) lets doctors track your heart rhythm while you go about daily activities. This non-invasive tool helps connect your symptoms to actual cardiac disturbances.

Doctors use AECG to detect several issues: linking symptoms to heart rhythm problems, identifying oxygen deprivation (ischemia), assessing risks after heart attacks, evaluating how medications affect your heart's electrical system, and checking implanted device function.

Several types of monitors exist for different situations. A Holter monitor records continuously for 24-72 hours when symptoms occur frequently. Event monitors record for 14-30 days when symptoms are less common. External loop recorders monitor for weeks to months, while external patch recorders work for 7-14 days using an adhesive attachment.

🔄 Monitoring Options: Your doctor will choose the right monitor based on how often your symptoms occur. Infrequent symptoms might require an implantable loop recorder that can monitor for 2-3 years!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

ECG Paper and Measurements

ECG paper isn't just ordinary graph paper – it's specifically designed to measure time and voltage. The paper has small squares (1mm × 1mm) and larger, heavy-lined squares (5mm × 5mm) that help interpret the readings.

On the horizontal axis (time), each small box represents 0.04 seconds, while each large box equals 0.20 seconds. This means 5 large boxes equal 1 second, and 30 large boxes represent 6 seconds of heart activity.

The vertical axis measures voltage (amplitude) in millivolts or millimeters. When looking at an ECG, you'll see the baseline (isoelectric line) – a straight line when no electrical activity is detected. Waveforms are movements away from this baseline, while segments are lines between waveforms. Multiple waveforms together form a complex.

⏱️ Time Check: When analyzing an ECG, the horizontal measurements tell you how fast events are happening, while vertical measurements show how strong the electrical signals are. Both are crucial for proper interpretation!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Normal ECG Waveforms

The P wave, representing atrial depolarization, should be smooth and rounded, less than 2.5mm in height and lasting less than 0.12 seconds. It's usually positive in most leads but may be biphasic (both positive and negative) in V1.

Q waves can be normal (physiologic) when less than 0.03 seconds, but abnormal (pathologic) when longer than 0.03 seconds or more than 30% of the following R wave's height. The R wave is the first positive deflection after the P wave and is always positive, while the S wave is always negative and follows the R wave. Together, the R and S waves represent ventricular depolarization.

A normal QRS complex has a duration of 0.075 to 0.11 seconds in adults, though its amplitude varies among leads. The T wave represents ventricular repolarization and typically moves in the opposite direction of the QRS. Normal T waves are slightly asymmetric and positive in most leads.

Wave Recognition: Learning to recognize normal waveform patterns is essential for spotting abnormalities. The shape, direction, and timing of each wave tells part of the heart's electrical story!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

ECG Segments and Intervals

ECG segments and intervals reveal crucial timing information about your heart's electrical cycle. The PR segment is the horizontal line between the P wave and QRS complex and should normally be flat (isoelectric). The ST segment, found between the QRS complex and T wave, represents early ventricular repolarization.

The J point marks where the QRS and ST segment meet. Doctors use this reference point to assess ST elevation or depression, which can indicate serious conditions like heart attacks.

The PR interval Pwave+PRsegmentP wave + PR segment measures 0.12 to 0.20 seconds in adults and reflects total supraventricular activity. Abnormal PR intervals signal problems: a long PR (>0.20 sec) suggests delayed impulse transmission through the atria, AV node, or AV bundle, while a short PR (<0.12 sec) may indicate the impulse originated abnormally close to the AV node.

📊 Interval Insight: The PR interval gets longer as you age, which is completely normal. Children typically have shorter PR intervals than adults, while older adults often have longer ones.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Measuring Heart Rate and Rhythm

Understanding how to measure heart rate from an ECG is a valuable skill. The QT interval spans from the beginning of the QRS complex to the end of the T wave and represents total ventricular activity.

To assess heart rates, we use specific patterns. The R-R interval (distance between consecutive R waves) helps determine ventricular rate and regularity, while the P-P interval (distance between consecutive P waves) reveals atrial rate and regularity.

Two main methods help calculate heart rate. The Large box method involves counting large boxes between consecutive waveforms RRorPPintervalsR-R or P-P intervals and dividing into 300. This works best for regular rhythms. For more accuracy, especially with irregular rhythms, the Small box method counts small boxes between consecutive waveforms and divides into 1500. It's more time-consuming but provides greater precision.

🧮 Quick Calculation: For a quick estimate of heart rate with a regular rhythm, count the number of large boxes between R waves and divide 300 by that number. For example, if there are 4 large boxes between R waves, the heart rate is 300 ÷ 4 = 75 beats per minute.



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The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

 

Physics

61

Nov 16, 2025

9 pages

Comprehensive Guide to EKG and Monitoring Devices

R

rylee helmholtz

@ryleehelmholtz_cfgo

Cardiac electrophysiology explores how the heart's electrical system works to create the coordinated contractions that pump blood throughout your body. This field helps doctors understand heart rhythm problems and provides ways to diagnose and treat various cardiac conditions. Let's explore... Show more

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Cardiac Cells and Their Properties

Ever wondered what makes your heart beat without you having to think about it? It's all about cardiac electrophysiology (EP), which examines your heart's electrical activity through specialized tests.

Your heart contains two main types of cells. Myocardial cells are the working cells responsible for contraction, while pacemaker cells are specialized cells that form electrical impulses spontaneously and control the heart's rhythm.

Cardiac cells have four key properties. Automaticity is the ability of pacemaker cells to create electrical impulses without outside stimulation. Excitability allows cardiac muscle cells to respond to stimuli, while conductivity enables them to receive and pass electrical signals to neighboring cells. Finally, contractility is their ability to shorten, creating the muscle contractions that pump blood.

💡 Did You Know? Over 200,000 catheter ablation procedures (a treatment for heart rhythm problems) were performed in Europe in 2013 alone, showing how important understanding cardiac electricity has become!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Cardiac Action Potential and Electrical Phases

The heart's electrical activity creates a measurable signal called the cardiac action potential. This energy moves electrolytes across cell membranes, creating current flow that appears as waveforms on an ECG.

The electrical cycle has three main phases. Polarization is the resting state, depolarization occurs during stimulation, and repolarization is when the cell returns to resting. On an ECG, you'll see these as distinct waves: the P wave (atrial depolarization), the QRS complex (ventricular depolarization), and the ST segment and T wave (ventricular repolarization).

After being stimulated, cardiac cells need recovery time called refractoriness. The Effective Refractory Period (ERP) is when cells absolutely cannot respond to stimulation. The Relative Refractory Period (RRP) follows, when cells might respond, but only to stronger-than-normal stimuli.

🔍 Key Insight: The configuration of the cardiac action potential varies depending on cell location and function. Fast response action potentials occur in atrial and ventricular working myocardial cells and His-Purkinje fibers.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

ECG Basics and Electrodes

An ECG provides valuable information about your heart's electrical activity. It can show the orientation of your heart in your chest, identify conduction problems, assess muscle mass, detect damage from lack of oxygen, and reveal how medications and electrolytes affect your heart electrically.

However, an ECG has limitations. It doesn't directly show the mechanical condition of your heart muscle - that requires checking pulse and blood pressure.

To record an ECG, electrodes are placed at specific locations on your chest. These connect to an ECG machine via cables that conduct current. The resulting leads record the electrical activity as voltage differences, allowing doctors to view your heart's electrical activity from different angles.

Remember This: While ECGs show electrical activity, they don't show mechanical function. Your heart might be electrically active but not pumping effectively!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

ECG Leads and What They Show

ECG leads work like different cameras capturing your heart's electrical activity from various angles. Standard limb leads (I, II, III) form Einthoven's triangle, with the right arm electrode always negative and left leg electrode always positive.

Lead I records between left arm (+) and right arm (-), viewing the lateral wall of your left ventricle. Lead II records between left leg (+) and right arm (-), showing the inferior surface. Lead III records between left leg (+) and left arm (-), also viewing the inferior surface.

The augmented limb leads (aVR, aVL, aVF) provide additional perspectives. aVL views from the left arm toward the lateral wall, aVR from the right shoulder (usually showing negative waveforms), and aVF from the left foot/leg toward the inferior surface.

📝 Quick Tip: Think of leads as different camera angles around your heart. Each lead captures a unique view, helping doctors spot problems that might only be visible from certain directions.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Ambulatory ECG Monitoring

Ambulatory electrocardiographic monitoring (AECG) lets doctors track your heart rhythm while you go about daily activities. This non-invasive tool helps connect your symptoms to actual cardiac disturbances.

Doctors use AECG to detect several issues: linking symptoms to heart rhythm problems, identifying oxygen deprivation (ischemia), assessing risks after heart attacks, evaluating how medications affect your heart's electrical system, and checking implanted device function.

Several types of monitors exist for different situations. A Holter monitor records continuously for 24-72 hours when symptoms occur frequently. Event monitors record for 14-30 days when symptoms are less common. External loop recorders monitor for weeks to months, while external patch recorders work for 7-14 days using an adhesive attachment.

🔄 Monitoring Options: Your doctor will choose the right monitor based on how often your symptoms occur. Infrequent symptoms might require an implantable loop recorder that can monitor for 2-3 years!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

ECG Paper and Measurements

ECG paper isn't just ordinary graph paper – it's specifically designed to measure time and voltage. The paper has small squares (1mm × 1mm) and larger, heavy-lined squares (5mm × 5mm) that help interpret the readings.

On the horizontal axis (time), each small box represents 0.04 seconds, while each large box equals 0.20 seconds. This means 5 large boxes equal 1 second, and 30 large boxes represent 6 seconds of heart activity.

The vertical axis measures voltage (amplitude) in millivolts or millimeters. When looking at an ECG, you'll see the baseline (isoelectric line) – a straight line when no electrical activity is detected. Waveforms are movements away from this baseline, while segments are lines between waveforms. Multiple waveforms together form a complex.

⏱️ Time Check: When analyzing an ECG, the horizontal measurements tell you how fast events are happening, while vertical measurements show how strong the electrical signals are. Both are crucial for proper interpretation!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Normal ECG Waveforms

The P wave, representing atrial depolarization, should be smooth and rounded, less than 2.5mm in height and lasting less than 0.12 seconds. It's usually positive in most leads but may be biphasic (both positive and negative) in V1.

Q waves can be normal (physiologic) when less than 0.03 seconds, but abnormal (pathologic) when longer than 0.03 seconds or more than 30% of the following R wave's height. The R wave is the first positive deflection after the P wave and is always positive, while the S wave is always negative and follows the R wave. Together, the R and S waves represent ventricular depolarization.

A normal QRS complex has a duration of 0.075 to 0.11 seconds in adults, though its amplitude varies among leads. The T wave represents ventricular repolarization and typically moves in the opposite direction of the QRS. Normal T waves are slightly asymmetric and positive in most leads.

Wave Recognition: Learning to recognize normal waveform patterns is essential for spotting abnormalities. The shape, direction, and timing of each wave tells part of the heart's electrical story!

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

ECG Segments and Intervals

ECG segments and intervals reveal crucial timing information about your heart's electrical cycle. The PR segment is the horizontal line between the P wave and QRS complex and should normally be flat (isoelectric). The ST segment, found between the QRS complex and T wave, represents early ventricular repolarization.

The J point marks where the QRS and ST segment meet. Doctors use this reference point to assess ST elevation or depression, which can indicate serious conditions like heart attacks.

The PR interval Pwave+PRsegmentP wave + PR segment measures 0.12 to 0.20 seconds in adults and reflects total supraventricular activity. Abnormal PR intervals signal problems: a long PR (>0.20 sec) suggests delayed impulse transmission through the atria, AV node, or AV bundle, while a short PR (<0.12 sec) may indicate the impulse originated abnormally close to the AV node.

📊 Interval Insight: The PR interval gets longer as you age, which is completely normal. Children typically have shorter PR intervals than adults, while older adults often have longer ones.

What is Cardiac Electrophysiologic study (EP)?
Also called Invasive cardiac electrophysiology
Series of tests that examine the heart's elect

Sign up to see the contentIt's free!

Access to all documents

Improve your grades

Join milions of students

By signing up you accept Terms of Service and Privacy Policy

Measuring Heart Rate and Rhythm

Understanding how to measure heart rate from an ECG is a valuable skill. The QT interval spans from the beginning of the QRS complex to the end of the T wave and represents total ventricular activity.

To assess heart rates, we use specific patterns. The R-R interval (distance between consecutive R waves) helps determine ventricular rate and regularity, while the P-P interval (distance between consecutive P waves) reveals atrial rate and regularity.

Two main methods help calculate heart rate. The Large box method involves counting large boxes between consecutive waveforms RRorPPintervalsR-R or P-P intervals and dividing into 300. This works best for regular rhythms. For more accuracy, especially with irregular rhythms, the Small box method counts small boxes between consecutive waveforms and divides into 1500. It's more time-consuming but provides greater precision.

🧮 Quick Calculation: For a quick estimate of heart rate with a regular rhythm, count the number of large boxes between R waves and divide 300 by that number. For example, if there are 4 large boxes between R waves, the heart rate is 300 ÷ 4 = 75 beats per minute.

We thought you’d never ask...

What is the Knowunity AI companion?

Our AI companion is specifically built for the needs of students. Based on the millions of content pieces we have on the platform we can provide truly meaningful and relevant answers to students. But its not only about answers, the companion is even more about guiding students through their daily learning challenges, with personalised study plans, quizzes or content pieces in the chat and 100% personalisation based on the students skills and developments.

Where can I download the Knowunity app?

You can download the app in the Google Play Store and in the Apple App Store.

Is Knowunity really free of charge?

That's right! Enjoy free access to study content, connect with fellow students, and get instant help – all at your fingertips.

Can't find what you're looking for? Explore other subjects.

Students love us — and so will you.

4.9/5

App Store

4.8/5

Google Play

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user

The app is very easy to use and well designed. I have found everything I was looking for so far and have been able to learn a lot from the presentations! I will definitely use the app for a class assignment! And of course it also helps a lot as an inspiration.

Stefan S

iOS user

This app is really great. There are so many study notes and help [...]. My problem subject is French, for example, and the app has so many options for help. Thanks to this app, I have improved my French. I would recommend it to anyone.

Samantha Klich

Android user

Wow, I am really amazed. I just tried the app because I've seen it advertised many times and was absolutely stunned. This app is THE HELP you want for school and above all, it offers so many things, such as workouts and fact sheets, which have been VERY helpful to me personally.

Anna

iOS user

I think it’s very much worth it and you’ll end up using it a lot once you get the hang of it and even after looking at others notes you can still ask your Artificial intelligence buddy the question and ask to simplify it if you still don’t get it!!! In the end I think it’s worth it 😊👍 ⚠️Also DID I MENTION ITS FREEE YOU DON’T HAVE TO PAY FOR ANYTHING AND STILL GET YOUR GRADES IN PERFECTLY❗️❗️⚠️

Thomas R

iOS user

Knowunity is the BEST app I’ve used in a minute. This is not an ai review or anything this is genuinely coming from a 7th grade student (I know 2011 im young) but dude this app is a 10/10 i have maintained a 3.8 gpa and have plenty of time for gaming. I love it and my mom is just happy I got good grades

Brad T

Android user

Not only did it help me find the answer but it also showed me alternative ways to solve it. I was horrible in math and science but now I have an a in both subjects. Thanks for the help🤍🤍

David K

iOS user

The app's just great! All I have to do is enter the topic in the search bar and I get the response real fast. I don't have to watch 10 YouTube videos to understand something, so I'm saving my time. Highly recommended!

Sudenaz Ocak

Android user

In school I was really bad at maths but thanks to the app, I am doing better now. I am so grateful that you made the app.

Greenlight Bonnie

Android user

I found this app a couple years ago and it has only gotten better since then. I really love it because it can help with written questions and photo questions. Also, it can find study guides that other people have made as well as flashcard sets and practice tests. The free version is also amazing for students who might not be able to afford it. Would 100% recommend

Aubrey

iOS user

Best app if you're in Highschool or Junior high. I have been using this app for 2 school years and it's the best, it's good if you don't have anyone to help you with school work.😋🩷🎀

Marco B

iOS user

THE QUIZES AND FLASHCARDS ARE SO USEFUL AND I LOVE THE SCHOOLGPT. IT ALSO IS LITREALLY LIKE CHATGPT BUT SMARTER!! HELPED ME WITH MY MASCARA PROBLEMS TOO!! AS WELL AS MY REAL SUBJECTS ! DUHHH 😍😁😲🤑💗✨🎀😮

Elisha

iOS user

This app is phenomenal down to the correct info and the various topics you can study! I greatly recommend it for people who struggle with procrastination and those who need homework help. It has been perfectly accurate for world 1 history as far as I’ve seen! Geometry too!

Paul T

iOS user