Ngmoco offers gamers a notional $3.50 to play We Rule

Demonstrating how virtual goods can be used to drive downloads, and those all-important future in-app purchases, ngmoco has given its most popular free-to-play game We Rule a marketing push.

The headline is that over three million kingdoms have been created in the iPhone and iPad game which was released globally on March 20.

Each kingdom requires users to have an account with ngmoco's Plus+ social network.

Users can have as many Plus+ accounts as they have email accounts, although the social nature of We Rule reduce the point of having multiple accounts, suggesting We Rule likely has three million users.

Back in April, I guestimated between one to four million installs on the basis of 400,000 daily users.

The promotion is being driven by a 25 percent sale on buying in-game items using the virtual currency, plus 20 free Mojo, which is the in-game resource you can buy with real cash.

The cost of Mojo varies depending on how much you purchase, but 5 Mojo costs 99c, €0.79 or 59p, and 30 Mojo $4.99, €3.99 or £2.99.

On that basis, the 20 Mojo ngmoco is handling out provides users with a notional value of $3.50.

It will be interesting to see how the campaign, which is open to all new players, and existing players who log into the game before Monday, August 9, 10am Pacific daylight time, boosts the game's position in the top grossing chart.