Just get NDS4IOS the best emulator for iPhone And iPad.
Extract the .ipa from the .rar and install it with IPA Installer or something else.
Magically acquire a .nds ROM file and copy it to the Documents folder in the nds4ios folder in /var/mobile/Applications (this is a lot easier with iExplorer or iTools rather than iFile).
Open nds4ios and the ROM should appear there.
- Emulator for iPhone and iPad
- Play NDS games
- Easy to install
- No jailbreak required
- Get fun with Nintendo games
- Dropbox synchronization