If the buttons do nothing

1. They use the sidestore:// and altstore:// URL schemes. If you don't have that app installed, iOS has nothing to hand the link to and shows an error.
2. Copy the URL above instead.
3. In SideStore or AltStore: Browse → Sources (top right) → + → paste.

Before you install

• Ammy is a sender, not a destination. It reads your now-playing track and POSTs it as JSON to an HTTPS endpoint you set — so you need something running at the other end to receive it. It is built to pair with Issun, and is not limited to it: anything that accepts an HTTPS POST works.
• Setup on the phone is an address and an optional key, and nothing else. Standing something up to receive it is the part that takes a moment — read the repo before installing, or the app will sit there doing nothing.
• You need SideStore (or AltStore) already set up with your own Apple ID.
• On a free Apple ID, sideloaded apps stop working after 7 days until refreshed, and count against a 3-app limit. That's an Apple restriction, not something this app can opt out of.