What kind of graphics? - for charts on android, http://code.google.com/p/afreechart/ - for maths calculations, http://commons.apache.org/math/ - for opengl graphics on android, it's already a pain with all the fragmentation here. There's OpenglES10 (but no longer implemented on Xoom), OpenglES20 (2.2/2.3 and up, but no VBO support on 2.2), Renderscript (3.0 and up), JNI (if you want to program in C), MonoAndroid (for mono, you need to pay for that though)... - otherwise, just go with the official Canvas API http://developer.android.com/guide/topics/graphics/index.htm...