David Maestri created Facebook's most successful widget, Mob Wars, but now he's in legal trouble because he developed and launched the app while working for the company that would become the Social Gaming Network.Sources tell VentureBeat that Maestri's Mob Wars, a role-playing game for the Facebook platform, earns its creator $1 million a month off its 2,505,698 monthly active users, mostly by selling in-game player upgrades for real world cash. On top of that income, research firm DeveloperAnalytics says Mob Wars could make another $22,000 month selling ads because its users load the app's pages around 60 times a day. Trouble is, Maestri developed and launched Mob Wars in January, before quit software developer Freewebs in February. After watching Maestri rake in the cash for months, Freewebs — now called Social Games Network — finally sued Maestri on August 11, alleging breach of contract, breach of duty, misappropriation of trade secrets and interference with business relations. Maestri told VentureBeat that "Mob Wars is my creation and the legal process is moving forward."