To continue the last post about GENPlusDroid real time rewind:

This uses the exact same method. Required some small changes to the emulation core, nothing major just how it loads/saves its state. The FCEU state saves are around 75Kb per frame. We are using a 20MB heap for the NES version which only provides 15-20s of rewind as you see in the final segment of the video.
Certainly more fun to real time rewind NES that Genesis in my honest opinion.
Download:
https://market.android.com/details?id=ca.halsafar.nesdroid
QR Code:

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