SugarDS v1.0 is an Amstrad CPC emulator for Nintendo DS and DSi by Nige Rideout (github). This version features :

• Improved Z80 / CRTC timing so more games run more correctly.
• Improved Mode 2 rendering so it's a little better positioned 'compressed' on the DS screen.
• Improved default key mapping that maps Y button to Joystick Fire 2 (used by many homebrews).
• Another round of improvements for FDC handling of two-sided disks. Orion Prime no longer warns of disk issues, Batman Forever 3.5" loads.
• Fixed the sound mute handler so that there are less frequent pops/clicks when loading up new games.
• Improved auto-load detection - more disks load the correct file more often.
• Lots of small cleanups and commenting of the code.

And if you are curious and you go check his Github profile, you will see that he has written several other emulators for Nintendo DS and DSi.