nds4droid is a Arcade App for Android developed by Jeffrey Quesnelle.
Download the latest version (7) of the apk here, in apksmods released February 12, 2016
nds4droid apk & mod has been downloaded 10,000,000+ since February 12, 2016. Is Free and the file size is 4.15 MB. does not offer in app purchases, users rated it with 3.1/5 stars with over 115109 ratings.
Finally, a free, open source Nintendo DS emulator for Android.
nds4droid is a free Nintendo DS emulator. It is still in it's infancy but supports many features you'd expect like save states and sound. It also supports the OUYA game console.
The nds4droid FAQ can be found here: http://jeffq.com/blog/nds4droid-faq/
Unlike other DS emulators nds4droid does not not violate the GPL, and it's completely open source.
Unfortunately, Nintendo DS emulation is still somewhat slow, even on higher end phones, but we'll continue to make improvements :). If you're having trouble with performance, try different "frame skip" options.