We’ve not come across the Mac version of Cadenza before, but it sounds fascinating: an app that listens to you playing an instrument, and accompanies you with a “real” orchestra. It’s the work of a startup called Sonation, which has a catalogue of classical works from the likes of Bach, Beethoven and Mozart, supporting instruments like the violin, cello and oboe. Now Sonation is trying to take the idea to iPhone and iPad as an app for use on the go – as well as improving its technology so it can accompany people singing, rather than just playing an instrument. The company is seeking $25,000 from backers on Kickstarter, and with a week to go is already on more than $19,700 in pledges. “Cadenza is unique—It’s the only app that listens to you, anticipates how you’re going to play, and adapts to you in real time. And the precision is uncanny. The app learns from you, fitting your playing better each time,” explains its pitch.