The Game Boy Advance had a D-pad, A, B, L, R, Start, and Select buttons. Java phones relied on the standard T9 numeric keypad. Mapping controls to keys like 2 (Up), 8 (Down), 4 (Left), 6 (Right), 5 (A), and 0 (B) was a clunky but necessary compromise for mobile trainers. The Legacy of Retro Mobile Gaming
Set the resolution to 240x320, enable "Scale to fit" and "Keep aspect ratio" to ensure the game looks right. Key Tips for Playing pokemon ruby java games 240x320 jar