Google translate

I always get a local SIM card so I have it available. If not, almost everywhere has wifi. Have a translation asking for wifi and password (mot de passe I think in French). Once you have wifi, you can use Google translate as much as you need.

Yes, download the languages you want on wifi. After that, it works perfectly offline.

how to:

https://support.google.com/translate/answer/6142473?co=GENIE.Platform%3DAndroid&hl=en

And do not 100% trust it. Google translate (or any other translation app) is usually correct, but it can get things totally wrong. In complicated sentences it can get it totally wrong.
If you mis-spell something, it won't subconsciously guess like a human being, it will totally garble the translation.

sally,

To second what Chris said, don't trust Google Translate implicitly as it's sometimes not accurate and sometimes completely wrong! Over the past year or two, I've been able to test it with both native French and Italian speakers, and the most common reply is that "it's close and somewhat gets the meaning across". I've also gotten "that's completely wrong" responses.

Google Translate primarily works online, so if you have a data plan for your phone you won't need to download anything. If you want to use it in offline-mode, you can download languages (I don't believe all languages are available for download). When downloading languages, be sure to keep the memory capacity of your phone in mind.

Google Translate has never been advertised as the equivalent of the Star Trek Universal Translator. Instead it's a tool that one can use as a last resort when educating guessing, pointing, and primitive sign language all fail. Personally I mostly use the camera feature most often to translate restaurant menus, and nutrition/ingredient labels at the supermarket.

I think it would be better to bring along some pages of words and phrases that you might commonly need, instead of relying on Google translate, which is often way off the mark.
Most any guide book will have the most-used vocabulary in the back pages, so just rip those out and take them with you.
Most people - especially people in the service industry - will speak English to you, so you won't have to worry.
And if all else fails, just point.

Thanks everybody. I already downloaded the languages in google translate just in case but also has some phrases that will come in handy.