Pacer is an activity tracker app, that works like a pedometer. I tried out Pacer for about a week and ended up deleting it. The app itself wasn't to bad. The pedometer aspect worked well enough. I liked the goal feature, along with some of the element. My problem with the app the syncing with My Fitness Pal. My workout from the previous day was being posted on the current day's exercise. The one other issue was it killed the battery on my phone, twice as fast as normal. I couldn't figure out how to fix it, so I decided to try one of the many other apps. If you're looking for a good basic activity tracker then give this a shot but it just didn't work for what I needed.
Disclaimer: Pacer logo is trademarked by the company. I do not have any affiliation with the company.