It’s that time of year again when millions of us in the U.S. make New Year’s resolutions to improve ourselves in some grand way – often by means of getting in shape and/or leading an overall healthier lifestyle. And this year we’re sticking to it – right? Well, at least until mid-February.

Fortunately this year there are dozens of free mobile health apps that can help us with our resolutions - or at least make it more fun trying.  There’s literally an app for everything from helping you lose weight to tracking your menstrual cycle, monitoring your heart rate, and evaluating your sleep patterns.

As a proud new owner of the latest iPhone, I am always looking for an excuse to download new apps. And what better excuse could there be than to make using mobile apps part of my job by writing a weekly blog review of a new mHealth app?

This week I compared three relatively simple apps designed to monitor your heart rate using the camera feature on your phone.

I began by installing the free Heart Fitness app by Senscare. As directed, I measured my heart rate with the app after I had been in a sitting position for at least 5 minutes. In less than a minute the app determined my average heart rate to be 91.8 beats per minute, indicating my fitness level is somewhere between average and poor. According to Heart Fitness, anywhere between 60 and 100 would be considered normal for an adult while a well-trained athlete should fall between 40 and 60 beats per minute. Other features of this app allow you to enter body information to boost the accuracy of the results; and for 99 cents you can get additional information, including a cardiovascular risk estimation.

Next I installed the free version of Instant Heart Rate by Modula. Like the Heart Fitness app, Heart Rate also has a 99-cent version with added features, but the basic fingertip measurement component is free. Again, my heart rate was 91 BPM, and according to this app, that puts me in the poor range by 1 BPM (60 to 90 is considered normal by Modula’s Heart Rate app).

The third heart rate app I tried was simply called Heart Rate by Chris Greening, CMG Research. This one was a little less exciting than the first two and it did not tell me when to stop taking the measurement. I got the impression that it would just continue to measure my heart rate until I removed my finger tip from the phone's camera lens.  I liked the first two heart rate apps better because they both measured my BPM for a set time, which was about a minute or less.

Next week I’ll review an app called Sleep Cycle designed to monitor your movement during sleep and wakes you up while you are in your lightest sleep phase so that you feel rested and relaxed.