The App Store is often filled with applications that have names that are vague enough to let you believe that they are going to do something that would likely be impossible. This has been incredibly true of iPhone battery applications that often sound as though they are going to extend iPhone battery life.
Instead of actually extending iPhone battery life they often provide iPhone battery images, tips for extending iPhone battery life, and other marginal features. Battery Magic, the free iPhone application version, is an application that essentially tells you how much iPhone battery life you have and the amount of time you have for different tasks.
This is listed as how long you have for 3D game play, regular gameplay, talk time, 3G or Wi-Fi internet use, video and audio playback, and standby time. Battery Magic is what it is and that is a very minor benefit beyond the basic understanding of how your iPhone battery life is distributed and then telling you your basic battery position. Instead you may just go ahead and maintain your iPhone's normal functions, unless you absolutely must see exactly how many minutes you can play Final Fantasy.
Battery Magic is really just an excuse to place banner ads and get brief periods of use as people will not maintain this app under most circumstances. Battery Magic is not a terrible application, but it really just lacks enough features to recommend.