[nazgul17]

A simple and concrete example is, go to Japan, find yourself in need of using any Japanese-only app, be extremely frustrated in not even being able to select text to translate it.

At least in recent versions of Android there is that OCR (?) powered functionality to select text when you're in switch-app view.

[crazygringo]

Thank you for the example!

I would suggest that these days you'd be much better off taking a screenshot and putting that into Google Translate.

That way all the text remains in-place, and you can keep it as a visual reference to refer to.

If you were selecting text, it would wind up in a kind of jumble that would be much harder to use.

[umbra07]

Circle to Search can translate everything on your screen without you needing to go through the whole "copy text, open Translate, paste, switch back to app" workflow. You just hold the home button, then press the translate button.