Cardiio: Heart Rate Monitor

• Weekly Pro Upgrade — $6.99/week
• Weekly Pro Upgrade — $39.99/year ($3.33/mo)
• Calorie-Burn Estimator — $4.99
• Coach Max — $1.99
• Full Pro Upgrade! — $9.99
• Hypothetical Life Expectancy Pack — $4.99
• Pulse Waveform Pack — $7.99
• Remove Promo Banner — $4.99
• Specific Heart Rate Pack — $4.99
• Target Heart Rate Pack — $4.99

Last verified 30 Sep 2026

4.7 58436 ratings · App Store

1. 5/5Extremely Accurate!

   I tried several deferent apps , some ridiculously expensive, asking for yearly subscription (Don’t know what for). None of were as accurate as this Cardiio app. and I am using the FREE VERSION. For ONLY A ONE TIME FEE OF $9.99 you can add 6 or 7 more useful features, but if you decide to have the free version, that would be good enough, There would be No pop ups of advertisement or anything like that. I really like the fact that makers of this app are very honest people. Thank you. P.S I READ AMOUNG SOME REVIEWS THAT THE PULSE READER ONLY WORKS LIKE 5 PERCENT OF THE TIMES. TO ME, THAT IS A GOOD THING, BECAUSE IT WANTS TO MAKE SURE THAT THE READING OF PULSE IS ACCURATE . SPECIFICALLY IF YOUR FINGERS ARE COLD OR DIRTY OR THE CAMERA LENS IS DIRTY. BUT ON MY CASE IT WAS THE COLD FINGERS. JUST PLACE THE FINGER UNDER YOUR ARM FOR FEW SECOND TO GET WARM AND TRY AGAIN . FOR ME, IT WORKED EVERY TIME.

   Shane1341 · 30 Sep 2026

2. 1/5Doesn’t work with iPhone 11 Pro Max

   Beware - this app simply doesn’t work with the flagship Apple iPhone 11 Pro Max. The problem seems to be the three cameras built into the iPhone 11 Pro Max. I contacted the help desk who in turn simply replied that I should read the directions. Either the help desk people don’t realize their own app directions are no longer up to date for current versions of iPhone, or I hope I’m wrong but perhaps they simply don’t care about customers of this app any longer. The app directions only refer to iPhones with a single camera. If it was just experimenting with placing my finger over one of the three cameras of the iPhone 11 Pro Max, or some combination of cameras, I wouldn’t have had to see if the help desk could actually “help” a customer. If you’re using most any version of iPhone less than the iPhone 11 Pro Max, this app is fantastic and works well. I hope the developer decides to update this app for Apple’s flagship iPhone. I also hope the help desk procedures get updated to provide actual help to customers.

   Lowthers8 · 30 Sep 2026

3. 5/5Been using for several years…

   I put this app on my phone several years ago, and used it regularly, and when my AFib got better, I didn’t use it much. Then my heart went completely out of rhythm, and for a couple of months, I wore a monitor, had an ablation, and finally have it back in some semblance working order. I rely on Cardiio every day, several times a day just for a quick heart rate. I did not pay any extra, just have the free version and that is more than enough to keep my mind at ease. This is a great app, especially for my new iPhone SE, with just the simple camera. I keep an image of my reading, and have a folder of my daily readings! Thanks, Cardiio!!

   Mawdine · 30 Sep 2026

4. 1/5Paid 7.99 for the waveform measurement

   I paid for the waveform measurement thinking it would give a little more detail about what is seen in the heart rate, like maybe a missing p wave, or too long a length between certain parts of the waveform...you know, length of time to the T wave or whatever. I didn’t expect the only information shown after 7.99 (a lot by app standards) to only say: -.2 sec. <—-that’s it. That’s what you get for 7.99. Okay? How is that even remotely worth any money at all and how does that help me? I downloaded the app and would pay 50 bucks if it helped me figure out why I get breathless for no reason after never smoking and while just sitting. People downloading heart rate apps have heart rate questions. I don’t expect it to be a doctor in an app. But I do expect 7.99 to measure something resembling anything. I feel betrayed. I feel stupid for parting with that much money. I made an assumption that 7.99 meant the waveform was analyzed. It’s not.

   steph0468 · 30 Sep 2026

5. 4/5Cute, very useful app

   Great app for medium-intensity workouts (which is a relative term, as with most things). The pulse taking capability is a joke - works about 5% of the time no matter how well you try to follow their directions. I also find it cute how they say this is a 7 minute workout when it actually lasts 8 minutes, whoever added the durations of the sets and pauses must have skipped arithmetic class and was too bored to actually time it with a stopwatch. These are minor things though (don’t care much about the pulse rate) and they don’t detract from the usefulness of the app, the smartly designed and well thought-out workout, and the convenience it gives you to do it anytime, anywhere. I enjoy it every time I use it - kudos to the developers.

   calincostian · 30 Sep 2026

Privacy

• Data Not Collected Developer declared

Accessibility

No accessibility labels collected yet.