GYM MixUp
Music and motivational voices, cut to the beat.
I built this for myself and I use it at the gym. The app runs on my iPhone, an engine on my Mac assembles each session from a 103-track library and a set of voice clips, and rendered sessions sit on the phone so they play with no signal. It is not published and it is only for my own use. What this page links to is a demo: the same player in a browser, running six sessions the engine rendered in advance. Every control on it is real, which is why it is worth showing.
Key Features
The engine builds the mix
It reads each track's structure and drops a voice clip where the beat lands, instead of playing a fixed playlist.
The screen follows the audio
Drop countdown, subtitles, energy timeline and beat markers all read from one playhead, so a scrub never desyncs them.
Skip by meaning, not seconds
Jump straight to the next beat drop or the next voice. Thirty-second nudges and a draggable timeline are there too.
Six modes
Warm up, Hard, Sets, Steady, Dark and Cool down. Each one is a different energy arc rather than the same mix under a different name, and Cool down carries no voices at all.
What the demo does
- Plays any of the six modes, 30 minutes each
- Skips drop to drop, or voice to voice
- Scrubs the timeline with the subtitles following
- Runs every control the handset has
What the app adds
- Builds a new session on demand, never the same twice
- Different tracks and voices on every build
- Downloads a session to play with no signal
- Records a set with the session still running
Built for myself, not published
The app is finished and I use it. It is on my own phone rather than a store, so this page is a demo instead of a download: six sessions the engine rendered in advance, which is why every control on the page works. Building a new one needs the engine that reads the library, analyses each track and renders the audio, and that does not run in a browser.