Social games firm FreshPlanet has launched a Premium version of its increasingly popular Song Pop game on iOS.

People paying up front for the previously-freemium game get better quality audio, more matches at once, and no ads.

However, what’s more interesting is its growth. Song Pop now has 1.9 daily active users (DAUs) across iOS, Android and Facebook, having added 400k in the last week.

Some way to catch up with Zynga’s Draw Something, then, which currently has 4.4m DAUs but lost 400k in the last week as part of an ongoing slump.

Do some mischievous sums to find the prospect, if both games continue their current trajectories, of Song Pop overtaking Draw Something in four weeks’ time…