As mobile games get closer to the scale of PC MMOGs, so they're taking on many of the features of their larger, older brethren.

One key element is having a large but closed beta test rather than soft launching in a couple of countries as many mobile games currently do.

It's something German developer Fishlabs is learning from with its forthcoming game Galaxy on Fire: Alliances.

World of possibilities

When it announced the closed program, it received more than 120,000 requests, which it's filtered down to 30,000 players.

The beta test for the iOS version being handled through the Testflight platform, with players given a daily allocation of premium currency so Fishlabs also gets an idea about monetisation.

And certainly the game is demonstrating good retention.

Fishlabs says that the average player is clocking up 14 sessions per day, while 35 percent of beta testers have played daily during the past month.

Indeed, Fishlabs is so pleased with the test, it's decided to push back the planned open beta into November.

Galaxy on Fire: Alliances will be released on iOS in Q1 2014, with the Android version following later.