Phone Off/Still Usable?

[sickle79]

I have two android phone I no longer use n I heard they can still be usable with the free call/ texts app. How does that work?
Sent From HTC Evo Design 4g from Boost Mobile using Android Central Forums

 

[GiantJay]

As long as you have wifi just download apps and the text in app or call app uses wifi. You can use Google voice too.

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