BPM app with spotify

Job ID: 35083716

Budget: €750 – €1,500 EUR

An app that downloads and plays playlists from its own spotify and sorts the songs by BMP. In a slider you set the desired tempo and appeal filters this out. Features like shuffle, fast forward, only play X seconds of each song, queue and remote control hotkeys. You yourself should also be able to go in and change the BMP setting for each song as this is not always correct.
There is an app for this purpose today that stopped working a few months ago, tempofy. See it for examples.

I don't know how it works but I want there to be an in app purchase for a monthly subscription. As I understand this is something that is in the app and not in the app store?
Related categories: Mobile App Development iPhone Android Objective C iPad