One month of use, and 100% flawless performance.

I bought this app one month ago specifically to use with my brand new Apple Watch Sport. It has worked flawlessly and here are my system specs (so you can compare it to what you have):
1. Apple Watch Sport, Space Grey, purchased new on February 10, 2016.

2. iPhone 6, 16 gb space grey, purchased new on September 10, 2015.

So, as I mentioned, this app hasnt given me any problems so far. I have had no problems whatsoever syncing the watch data to my iPhone (as a lot of people here talk about) and the app accurately records my biometrics throughout the night as long as I have it on the highest sensitivity (because, after experimenting with this app, I had no idea that I move around a TON when I sleep.) One concern is that the app uses anywhere between 20-30% battery life (Apple Watch) each night. However, my watch lasts the entire next day and usually has at least 20-25% battery life remaining just before I plug it in every evening.

To be honest, I believe a lot of people here have problems with this app due to outdated hardware or not updating their OS constantly. Come on people! This is 2016! Throw away those dumb iPhone 4s and 5s! Get with the program.

Sean C... about Sleep Tracker - Sleep Pulse 3