The heartless are meanier, yeah... it is kinda difficult, but once you get used to the MOST ANOYING controls and the WORST cammera you will have no problems beating them.
The sound effects are bugsy and the game has a lot of loading time and glitches.
The main characters are the same as the GBA/PS2 versions, the brave Sora, the mighty Donald Duck and the charismatic Goofy, and Jiminy Cricket
Donald, Goofy, Sora, and Jiminy Cricket were traveling across the universe when they decided to grab some shut-eye, and so they put the Gummi ship on autopilot. In their sleep, a strange creature crept undetected to the vessel and subsumed the dreams of Sora, who then wakes up alone on an island. It's actually called Swashbuckler's Island, but there are no swashbucklers to be found here...just a parrot, who says that it's probably a good idea to look around and gather stuff to make a raft so you can shove off. The island itself looks fairly bland, minus an inexplicable lava pit and a strange altar among the high rocks.
Overall: Kingdom Hearts is a mediocre Mobile version for your cell phone, you may want to avoid it.