In addition to the Android tips, in iOS you can screenshot and then translate in the screenshot. Then press the X to discard the screenshot and return.

If you have Google translate, Android has a feature where a long press on the home button gives you a translate option.

No, although you might be able to translate using your phone, e.g. on my Android I can use the "scroll and translate" feature (I'm not sure if it's sent to Google or if it's done on your phone, so you might find the privacy implications a deal-breaker).

With ich_iel, I remember someone on Lemmy explaining that the German is translated from English in a very literal way, so it's not at all idiomatic or even coherent German. Perhaps machine translation would cope with that just fine, or it might completely fail, but I think you'd lose what makes it funny.