From GameBrew - a wiki dedicated to Video Game Homebrew.
An application to check whether a surface is level or not, it makes use of the DSMotion card and DSerial card. It is written in C++ and inspired by a similar application on the HTC Diamond phone.
For user who does not own an DSMotion or DSerial card, level check will not be available. User will only be able to move the bubbles with buttons.
D-pad - move bubbles
Tested on the NDS with a DSMotion card
GFX were ripped from the internet and fed through PAGfx.