nds4droid is a free, open source Nintendo DS emulator written for Android smartphones. It is based off of the excellent emulator DeSmuME. The source code can be found on GitHub.
- Download the latest version, release 47: nds4droid-47.apk or get it on Google Play
Answers to frequently asked questions can be found here: nds4droid FAQ
nds4droid is free and has no ads.