There's nothing journalists like better than to categorise things into neat little boxes.

On that basis, if companies such as TinyCo, Pocket Gems and Storm8 were among the first wave of social mobile gaming, the second wave has seen the rise of core oriented companies such as Supercell and Kabam, alongside the likes of Zynga and Backflip, who remain casual-focused.

But what's next?

The new new wave

Much more diversification, obviously, with both the core and casual categories fragmenting into ultra-core, mid-core and myriad flavours of casual.

It's the latter that San Francisco start up Thumper Studios is looking towards.

Formed by developers previously with TinyCo and OpenFeint, it certainly knows the casual social mobile scene.

"We've seen the success of asynchronous head-to-head games like Words with Friends, SongPop and Draw Something," says Jennifer Lu, previously business developer director with TinyCo.

"We're looking to bring that dynamic to larger groups of players."

Open door policy

Her argument is that in the real world, 'game nights' see the coming together of groups consisting of friends and friends of friends to play board and card games.

Some people come to play and some just come to socialise but by the end of the evening they're all interacting together and that makes the experience richer, she explains.

And that's the dynamic Thumper is looking to encourage with games for you and your friends, and also with random players who might become your friends. Not only will this make for more interesting experiences for players, it will ensure the games have a better chance of being spread virally - still one of the biggest headaches for developers.

Half speed ahead

It's early days, of course, but Thumper's first attempt appears to be working. Despite some technical gremlins, WePlay was soft launched in early December on iOS and Android.

Based on simple mechanics of choosing from a set of phrases to complete a sentence and then voting on the funniest answer, WePlay has seen players, on average, adding three friends and sending 24 messages via the group in-game chat within the first 48 hours.

Each game session consists of between three to 12 players and can be generated at random or through your Facebook social graph. As with other such games, you can have multiple sessions operating simultaneously.

Lighting the touchpaper

So, at present, the five-strong development team is furiously iterating the game, with a harder launch planned for the end of January.

Linked to this is the issue of funding. Thumper completed an angel round, gaining cash from the likes of RedOctane co-founder Kai Huang, BigPoint CEO Heiko Hubertz and IGN co-founder Mark Jung. It will looking to raise its first round proper to staff up further.

For according to Lu, the opportunity is while other companies are competing in the mid-core mobile space, there remains plenty of opportunity for casual social gaming.

"There's a lot of learning and iteration to do because it's novel," she says. "No one knows what's going to work in this market. That's why it's exciting."

You can check out what Thumper Studios gets up to via its website.