PaintCAD - image editor for pixel art and drawing.
You can draw in 24bpp mode (16 million colors) and 8bpp mode (256 colors with index palette).
You can edit BMP, GIF, PNG, you can create animated GIFs, you can draw PNGs with semitransparency (alpha channel), you can create and use your own raster PCF fonts.
Get it on Google Play: https://play.google.com/store/apps/details?id=org.microemu.android.paintcad.PaintCAD
Video tutorial about simple drawing in PaintCAD Mobile: http://www.youtube.com/watch?v=e-kqMxna1s4
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