Good to know: How to avoid costly running up costly bills on iPhone, iPad and Android apps

From the Telegraph:

A five-year-old boy has run up a £1,700 bill in just ten minutes while playing on his parents' iPad. Danny Kitchen asked for the passcode for the device so that he could download a game, Zombie v Ninja, from the Apple store. But after downloading the free app Danny found his way into the game's online store and innocently ordered dozens of costly add-ons - totalling £1,710.43.
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