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Opens Google Translate (the app if installed) with your text filled in — needs data. Show big displays what you typed full-screen, handy for a hotel name or address.
Tabi Phrasebook gives you polite, practical Japanese for the moments that come up on a trip, like finding the right platform or explaining an allergy. Pick a situation, then read the phrase aloud using the romaji, or tap Show to staff to display it in large Japanese text.
It's free with no sign-up. Add it to your home screen and the phrasebook keeps working when you have no signal.
Each guide lists the phrases for one situation, with notes on what to expect in Japan.