4 stars: Fun, even if you use the free version. Lots of good causes to donate steps to, some cool freebies now and again, and fun to watch your steps accumulate. Sometimes, even with location on, the boost won't track extra steps (this is when I'm dog-walking). Which is probably because of the stop and go of the walk...but it's definitely still exercise. Would love to see Fitbit integration, etc. Four stars now, hopefully 5 in the future!
3 stars: I do like the app. I even pay for premium to double the coins I get. It just gets annoying when I do a flat out run for 20 minutes using the X2 boost and it just freezes when it's over and doesn't register anything at all. 4th time this has happened in the last 2 weeks and yes I have uninstalled and reinstalled it.
2 stars: Despite the addition of paid features, the app is less reliable at the time of this review than it was this time last year. On some days it claims I was walking around boosted while I was actually laying in bed. On most days it only counts 50% of my steps. Worse than all that, its ad service providers saves ads in your phone's cache and wastes your device's memory
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