I have a FreedomPop SIM which I want to use in a backup phone, but it is not compatible with my old HTC Desire (which is still running Android v2.3). Can anyone recommend a decent used smartphone which will run Android 4+ and can be bought for around £50? I'm not at all fussy about the condition of the phone - I just want something cheap, with at least a 4.7" display, that will run a fairly recent version of Android.
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