Delta Emulator is the successor to the legendary GBA4iOS emulator.
Delta
System(s): Nintendo DS
OS Supported: iOS
GBA, GBC, NDS, 3DS, N64, SNES, GameCube, Wii Emulators on Windows, MacOS, Android, iOS
DraStic is much better than nds4droid since it has more features or functions for nearly fully emulating a real NDS.
Pretendo is a free Nintendo DS emulator that lets you play your favorite DS games on any Android device.