Speedshifter

"So it's an OK app that shifts your tempo lower or higher to make it easier to play a chosen instrument. How you ask? It slows music down which let's you play along with the app. It's OK for £2.99. More features like lower and higher pitch could be added for external use. I would download it only if you had very little options. It's pretty basic and simple to use. I'd give it a 4 star."

"Excellent idea, some improvements handy: I have two needs not meet by this app: 1. Fine adjustment of the cutoffs on the track would be handy : perhaps an enlargement window in which one could do this, or a minutes: seconds input box. 2. I play a pre concert pitch instrument: fractional tone transpose would help."

"It doesn't differ a lot from the free version. I bought it so that my students could play backing tracks meant to be for Bb clarinet on an Eb clarinet, but you can only transpose up to three semitones up or down. Therefore transposing more than a minor third up or down is impossible. Having this facility would make the app a more valuable instrument."

"Unusable"

"It doesn't work with Android system"

"Mostly just didn't work at all, blank screen. When it did work would often not accept the music in any format including the one it asked for. Managed to get 1 piece to load up but it was so quiet I couldnt hear it above the music I was playing despite having it on several devices at max vol. Useless."

"Completely usless"

"Big disappointment! Clunky, slow and sometimes just will not work. Unresponsive. Seems as though it doesn't work with Android very well. Friends with Apple devices seem to think it is wonderful. Wish I hadn't bothered downloading it. Will be uninstalling."

"It has trouble while starting up everytime"

"Being able to slow a piece down for beginner pupils has always been needed. At last, technology has caught up with music teachers esential needs."