I just updated my NES Emulator to 2.2.5 and it keeps crashing after the update. It was working before the update. I found one thread about this problem on modmyifone.com.
It turns out the executable of NES emulator is not signed. Assuming you have a OpenSSH set up. You can ssh in your iPhone and sign the executable by yourself.
Here are the commands after you ssh in.
apt-get install ldid
ldid -S NES
Note that if you already have ldid installed, you don’t have to run the first command. You might need to reboot your iPhone after you run these commands. The first time I tried to run these commands, it didn’t work. I did it the second time and it finally worked.
[Update] A new version 2.3.0 just came out. You can use Cydia to get the updated version.