The MiniTycoon Casino iPhone app launched by US mobile gaming developer SGN for free only last month has reportedly hit the sweet spot among users, with the company claiming over 600 000 downloads from Apple’s iStore.

The game lets players build their own virtual casino, choosing from slots, roulette and card tables, and awards chips for the best designed venue.

SGN chief exec Randy Breen says that the popularity of the app has surpassed expectations. “As mobile social gaming continues to pick up steam among audiences, we expected MiniTycoon Casino to takeoff,” he said this week.  “However, we were surprised by its tremendous out-of-the-gate success.

“The appeal of MiniTycoon Casino is that it allows players to create the casino of their dreams and show them off to their friends as well as competing players. The new holiday themes expand the creative choices for players as they build their empires and cash in this holiday season.”

Breen revealed that MiniTycoon Casino players have banked nearly 300 billion chips in the game and, since it can support a high number of concurrent users’, gamers have been inviting friends to join in the action via Facebook or Twitter and post their achievements.

“The game is also connected to Game Center, Apple’s social game initiative on iPhone, allowing players to connect and share their progress and compete on the leaderboards,” he concluded.