Any mobile phone! Even a phone from your grandmother, if this is cellular ;) Seriously, though, it does not matter if you have an iPhone, Samsung, BlackBerry, a contracted Verizon phone or locked AT&T phone or even an old Nokia 250. In fact, iSocket and your phone are independent from each other. You only need a phone to accept text messages or calls about power outages and other alarm events - the same way as you accept messages and calls from your friends. Moreover, iSocket can send a voice message to a landline phone. You can manage your new Plug-and-Go iSocket from a computer if you don't have a smart phone.