US music apps developer Smule has released a new iPhone app – Sing! – and revealed some stats about its business. The company’s apps, which include the likes of Ocarina, I Am T-Pain, Magic Piano and AutoRap, have been installed 61m times so far. Meanwhile, in July those apps had 15m active users, and overall users have created more than 750m songs using them. Sing! is a follow-up to the company’s Glee Karaoke app, letting people sing along to popular songs and beam their hollerings to the world. 100 licensed tracks are included from the likes of Lady Gaga, Justin Bieber and Carly Rae Jepsen.