Whenever I open the note-taking app Saber (github link above, also on Fdroid and Playstore) a window appears telling me to decide if I want to have personalized advertisrments shown to me or not and demanding from me to update the app even though I can keep using it without any further problems.
Install Saber from F-Droid or use the FOSS release on GitHub. Those releases don’t include the Google ad library because it’s proprietary.