Sonic Mania J2ME

By Iso Kilo

Sonic Mania J2ME is a modification of the 2005 flip phone port of Sonic the Hedgehog.


The aim of the project is to showcase the development of Sonic 1 J2ME's research and reverse engineering and the evolution of the community. In it's current state, Sonic Mania J2ME is a graphics, audio, and text hack. Taking advantage of Sonic 1 J2ME's 256 color PNG graphics, and MIDI music, the hack gives it an upgrade using Sonic Mania's assets.

While Green Hill remains the same, aside from the graphical updates, Marble Zone and Spring Yard Zone are to be converted to Lava Reef Zone and Studiopolis (Though they are work in progresses)


  • 4/6 - Left/Right: Move left or right
  • 2 - Up: Jump
  • 1/3 - Up left/Up right: Jump left or right
  • 8 - Down: Crouch or roll if moving
  • 7/9 - Down left/Down right: Roll left or right
  • 5 - Center: Look up


  • JAR hack created by Iso Kilo
  • Promotional Sonic artwork by MeloSoni12 (Edits by Iso Kilo)
  • Art from Sonic Mania (Edits by Iso Kilo)
  • MIDIs pulled from


The J2ME platform is likely new to most, so included is an emulator, KEmulator, but you can use whatever J2ME emulator of your choice. Also some recommended settings:

  • Recommended resolution is 240x320
  • Limit to 30 FPS for a smooth but tolerable experience
  • Limit to 15 FPS for correct object and animation speeds

Setting the emulator to unlimited FPS will cause the game to run at rougly 300 FPS (Depends on the speed of your PC), making it a speedy, unplayable, ugly mess

KEmulator Download


  • Sonic 1 J2ME is what the infamous GBA port is based on, you can notice this through many similarities like the music, and the misuse of Marble Zone's switches in Spring Yard and Labyrinth
  • J2ME uses prototype assets from the Mega Drive version of Sonic 1, like the blinking lights in Spring Yard, and even some of Sonic's sprites
  • The game is split into 2 parts, and the parts are made by separate developers! Part 1 was by iFone (No relation to Apple), and part 2 was by Glu.
  • The code suggests the game was intended to be all together, rather than split
  • J2ME uses files straight from the original Sonic 1's source code
  • Sega seems to insist to use J2ME for any portable ports of Sonic 1, possibly because they no longer have the source for MD Sonic 1
  • Sonic Mania J2ME is the first J2ME hack in an SHC

File Type: rom/zip

File Size: 730.9 KB

Sonic The Fantastic @ 2020-10-26 05:48:49

100% loved it!

Sonic The Fantastic @ 2020-10-26 09:42:28

But it's sooooooooooooooooooo hard, I will keep trying though, So hold on to you're hat!

Eeveelover64 @ 2020-11-07 07:37:39

wrong form of your

DamienlaCritique @ 2020-10-28 09:50:48

I remember playing this on Nokia N8

emeraldlime @ 2020-11-03 11:15:50

Very nice! I tried to play it on Android using J2ME Loader, and it runs wery well!

Can't wait to see the full ported Sonic Mania to J2ME!

ninesogabox @ 2023-02-02 22:51:26

Why don't you put it in the Chinese version?

The Chinese version adds a touch screen function to the game in 640x360 resolution version

The actual game screen is still the same

But we added something similar to the half of NDS

Unfortunately, the Chinese version cannot use any code to save your files to part2