Travelling to a foreign country usually will require you to be familiar with the language of that country. You can easily get by without attempting to learn the local language but it is more impressive to the local if you at least tried. By all means book a tour if you are not confident but after a few tours it does become clear that you are more capable than you think.
Anyway I don’t use translator apps on the spot as they have not met my requirements. Also I don’t want to be distracted so someone might steel my phone! However I do learn the key phrases and listen to the spoken videos to at least get the basics of a language, with english translations of course.
The only App to use while overseas for language translation for iPhone, iPad or Android phones like the Samsung Galaxy series the best, most useful easy to use app is Google Translate, I can keep going on about how useful it is! The only flaw is that it requires data for the most useful features including the spoken translation. That said there are a number of downloaded language packs for the most popular languages for off line translations but that only works for words or phrases that you type in. I must ask warn you that the translation is literal so what you type in is what you get i.e. missing grammar and real world context.
Give the Google Translate a go before leaving the country and download the language packs.