That'll teach you to leave home without an iPhone charger.The Washington Post reports that an Apple exec has confirmed that there's no truth to the theory that closing open apps on your iPhone will prolong battery life. In fact, going in to shut down apps further drains the battery, since apps have to be reloaded later.The revelation came in an email exchange between Apple Senior Vice President Craig Federighi and a customer named Caleb. Federighi confirmed that apps don't affect iPhone battery life when they're not active — they freeze when not in use. That differs from many Android phones, like the Samsung Galaxy, which do benefit from shutting down running apps.As the Post notes, disabling location services or the Background App Refresh feature can help you avoid battery depletion.Beyond that, the best solution may be to simply bite the bullet and start traveling with a charger. We'd never dream of asking you to stop using your camera as a mirror or reconsider cyber-tracking your Uber driver's every move.