Open Note Scanner + OpenCV is a free and open source document scanner that turns your phone camera into a faux printer scanner for copying paperwork. It processes everything very nicely. Just play around with positioning and hold steady until the green overlay box properly crops the text body before hitting the button

I always download it through fdroid.

https://f-droid.org/packages/com.todobom.opennotescanner

Classy shark analyzes your apps for trackers. Its a good indicator of just how spooked and adridden each program is.

Invizipro is a great firewall+i2p+tor security app

Imagepipe is a powerful image editor and metadata remover

Seal is a YouTube downloader powered by yt-dlp

Termux let’s you emulate Linux to a decent degree

WolframAlpha is worth the price on the appstore.