SudoContest is Java based so runs on virtually any phone. You compete with all other players in a global ranking! Each month, you can participate in a contest. Your ranking is based on the time you need to solve a Sudoku. You can play as many times you like, and your best time counts! Three categories exist, i.e., peanuts (very easy), no worries (moderate), insane (hard). It is allowed to play in multiple categories.
Download SudoContest for free at GetJar.com:
JAD file (SudoContest.jad)
JAR file (SudoContest.jar)