Made on a plane, more or less

Tandem started in a boarding line. Two people, one laptop, one movie — and macOS would only play to one pair of headphones. The other person was stuck with nothing, or a single shared earbud.

So Tandem fixes the thing that's missing: it shares your Mac's sound to every pair of headphones at once, then adds the small comforts you'd want — one real master volume, per-device trim, saved groups, and a safe way to add a friend for the flight.

It's a single, paid Mac app. No subscription, no account, no data leaving your Mac. Just shared sound, the way it should have worked the first time.