I love big data, and have already come to trust this companys suite of apps so I wanted to give this a try. The claims of battery life are accurate in that it doesnt use a lot at all! It accurately tracks my day to day locations minus a few hiccups here and there, but this is accounted for in their FAQ. It wont always pick up everything but again, this is a high level view of your day. I wish it pulled workout activity from Apple health since I workout from home and this time is just lumped together with "home" category instead of its own category of time. But it does pull sleep activity and works seamlessly with the Sleep Cycle app. Great app!