Terms
Buy it once, run it on three Macs you own, ask for your money back within fourteen days if you don't like it. The rest is detail.
What you get
A licence to use Spine on up to three Macs, for as long as you want, with no renewal and no subscription. There is no trial version: you buy it, you paste the key, it runs. That is what the refund is for. You can release a machine from the app's Licence tab and use that slot somewhere else. The licence is yours; don't resell it, post it publicly or hand it to people outside your own desk.
Refunds
Since there is no trial, the refund is how you try it. Fourteen days, no explanation needed. Email hi@tryspine.app with your order number and the money goes back to the card you paid with. If the app simply doesn't work on your Mac, the refund stands whenever you ask — fourteen days or not.
Updates
Fixes and improvements to this version are free. If there's ever a paid major version, owners hear about it first and pay less.
Who you're buying from
Payments go through Polar, who are the merchant of record — they issue the invoice and handle the tax. Their terms cover the transaction; this page covers the software.
No warranty
Spine draws pictures on your desktop. It comes as is, with no warranty of any kind, and if something goes wrong the most that can be owed to you is what you paid. Don't use it anywhere a dimmed or distorted screen could hurt somebody.
Fair play
Don't pull the app apart to lift the shader, don't ship it inside something else, and don't route around the licence check. Everything else — filming it, writing about it, showing it to people — is actively encouraged. See the Reel offer.