[arvinsim]

Except some non-subscription software are still SaaS in disguise.

Take a look at Sketch. You can use a file on future versions...but up to a point. If you hit that limit, you will have to buy the upgrade.

[LegitShady]

I don't use sketch, so I don't know anything about it. It's mac only and while i have an ipad pro and an iphone, I don't own a mac and dont want one, and thats a mac only app.

I'm not sure why sketch would have the restrictions they have except that forever supporting old formats might be more expensive than they could justify.