Lemuroid Rom Pack | Verified

Lemuroid is a free, open-source emulator frontend for Android (also on some Linux handhelds). It supports 20+ systems:

"My NDS games are upside down/slow." Fix: Lemuroid uses the DraStic core for NDS. Go to Settings (inside Lemuroid) > System > Nintendo DS > Change the rendering resolution to 1x (Native). Also, check the "Screen Layout" option.