As designers and developers there is no greater sin than building an app that is a battery hog.
I recently read an article by David Smith that speaks to this idea. As David Smith puts it:
“We are building applications that run on handheld, battery powered computers that connect to the internet over wireless networks. Every watt that we can save will improve our customers’ experience.”
From a UX design perspective we have to be aware that our apps live as part of a larger ecosystem of apps, all of which share the same battery on the device. And nothing ruins the user’s experience more than being left with a lifeless iPhone with 0% remaining in battery life.
All the design, features, and functionality will be pointless if you don’t consider the first commandment of mobile design: “Thou shalt not screw with my battery life”