For in-browser ads, I recommend Firefox with uBlock Origin.
For in-app ads, using DNS-based ad blocking (AdGuard DNS, NextDNS and others) will work with apps that do not run their own ad network.
Finally, for apps with their own ad network, you can give ReVanced a try: it can patch apps like YouTube, Twitter, Twitch and Instagram to remove ads or add usability tweaks. Just keep in mind that they can decide to restrict access to patched apps whenever they want or even ban you (Instagram is notorious for banning or shadow-banning people toying with their API).