For me a huge amount of ram, internal storage, a battery that can last for a week, water-proof and unbreakable. And have customizable rom that can mimic any rom devices you want (i.e. sony, samsung, miui, CM or even iOS). (it's not hard to dream... )
the restricted ability to connect to a network. Apple has the multipeer connectivity feature which can essentially allow for worldwide connection almost free of cost. (I haven't read into it much so I may be very wrong). If internet connection was allowed such as the WiFi Freedom Tower during the Occupy movements. I'm sure this is far from likely to happen but it has been done small scale already.
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