Facebook is probably killing your iPhone’s battery – here’s how to fix it Facebook is easily one of the most popular third-party iPhone apps on the planet. As it turns out, it might also be one of the biggest culprits of iPhone battery drain, according to recent findings brought to light by a former Apple Store Genius. The good news, however, is that it is remarkably easy to stop Facebook from eating up your iPhone's battery, and in this post we'll show you how.