yes, it can block SOME ads in apps. it's also really good at breaking access to said apps too, then you must spend a great deal troublehsooting apps one at a time.
IMHO - ublock on the browser, pay for apps that have adfree versions, don't use apps that don't, and pirate the rest.
I have one ad supported app on my phone - the Overcast podcast player. That’s only because the author created his own non scummy ad network and I find ads on the podcast player that advertise other podcasts useful.
If I didn’t, I would pay him too to get rid of ads.
When I did buy Windows PCs, I either bought from the business division of Dell or the Microsoft store specifically because they weren’t bundled with adware.
On my Android I have Netguard[0] configured with a hosts file, Firefox with uBlock Origin and NextDNS with comprehensive blocklists.
uBlock Origin protects only one app — the browser.
It's just so faulty and pointless.
This is why piholes are awful. I don't know why they get such high praise - it's just a crappy DNS filter that blocks like what 40% of the ads you see?