Real talk from an /all browser: Why use an app that has ads at all? Why not use one of the many free apps that are available and do the exact same things?
I used Sync for about 10 years on Reddit. I really like the UI/UX, and I've grown accustomed to it.
I've tried Jerboa, but it feels clunky and is missing features. I do like to support FOSS projects, but it's not like Sync is some big business. It's one guy who's built up a pretty good app, and he's generally well trusted in the community.
Hey, use NextDNS. I use Sync too and I never see any ads.
Edit: also use DuckDuckGo's app blocker that is built into their browser. It stops apps from calling home when they're not running. Sync is a grievous offender and tries to call home 300-1000 times per day when it isn't running.