Smule – the company behind hugely successful iPhone app I Am T-Pain – has launched an official app for musical TV drama Glee. It costs $3 and is basically a connected karaoke app. Three songs are included – Rehab, Somebody to Love, and You Keep Me Hanging On – with more available for in-app purchase. Users sing along to the songs then share them with others, with a feature allowing multiple performances to be harmonised together. Smule has also included Auto-Tune technology.