Released on Tuesday, Tapulous’ Tap Tap Revenge 3 was #1 in Singapore a day later.
A day after that, it was at the top spot in the Netherlands, Australia, Canada, Mexico, the UK, and the US.
Which - the App Store's launch day excluding - must make the game the fastest to the most App Store #1 positions.
//note: it's since been pointed out that The Sims 3 was a US #1 in one day. Impressive considering its $9.99 price tag, although we don't think it was #1 on as many App Stores so quickly.
Of course, the fact that the previous games in the series have been downloaded over 15 million times and are played over two million times daily - making it the most popular game in App Store history - suggests we shouldn't be surprised about this.
What will be more significant however is when figures are revealed for its in-app micro-transactions.
It offers 6-song band packs at $2.99 and 2-song packs at 99c, as well as letting people buy virtual items for their avatars.
On that basis, Tap Tap Revenge should also be the first game on the App Store to make more money from micro-transactions than from the original game purchase - no matter how fast it's currently selling.