It’s free. It’s only on google play. The 20$ is to get rid of ads forever. There’s also a subscription model which I’m not a fan of but it only costs 17$/year.
I’m a sync user and I love sync because of the customisation and the UI. It was pretty much my perfect reddit app.
Why pay money for an app when there’s tens of apps which do the exact same thing but don’t include ads in the first place?
To me, it’s because the app is so polished and customizable. Other apps don’t really come close yet, but they might soon.
Pepsi, Coke, or Budget no-name cola? Windows, MacOS, or Linux? Sometimes it’s a personal preference.
I like the UX of Sync. I’ve made QOL feature requests in the past and they’ve been implemented. For an early beta, it’s extremely well polished. I can afford to support the developer for a quality app, so I do.
I can certainly see the merits of each app, and have used a few of them. I just prefer Sync.
But that’s me. It should have no bearing on what you or anyone else uses.
Give me a free coke clone and I’ll pick it most of the time. Your comparison lacks because everything has to be bought (except Linux).
FOSS apps are free and will always be free.
But yeah, if you prefer one app over another and you’re fine with paying money to use it, go ahead.