A soundtrack has to outlive the launch, so a licence that lapses is no use to a game that ships once and sells for years. Licences here are perpetual and attach to a registered game title: once a track is in your game, it stays there.
PC, mobile, browser and console. The boundary is the studio, not the store: a solo developer shipping to Switch is on the same self-serve licence as one shipping to itch.io.
The licence is attached to one registered game title and does not expire. It also covers in-game use and the game's own organic trailers.
Self-published studios under 200,000 dollars in annual revenue or funding buy directly. Publisher deals, work-for-hire and AAA are quoted instead, because those are genuinely different agreements.
Take a single track for a game jam entry or a one-loop mobile game, or a five-track pack with extra tracks added as you need them, up to twenty tracks in one title.