Introduction
When 54 percent of the internet traffic share is accounted for by Mobile, it's certainly nontrivial to acknowledge how your app can make a difference to that of the competitor!
Once you're done with the app development and all looks good on the simulators and internal network devices—but out there in the wild, with bandwidth restrictions, TCP congestion, cache hit/miss, the device configuration, your user may not experience what you intend to provide & not every unhappy customer leaves feedback; they just stop coming.