I tried this app and I noticed the translation is a bit funny. I translated from English to my native language and noticed few errors and funny sentences. It looks a bit like google translator did it. I had to uninstall the app I'm afraid.

It translates well... however on each page you click, the webpage turns back to its original lenguaje and you must re-click the change lenguaje button.

Warning!!!!!!! Guys please read this review in FULL. I suspect people who post positive reviews do not speak a second language. I am a Native English speaker but I also speak fluent French, Spanish and Portuguese. This app basically uses google translate and it the translations are not correct at all. There are mistakes everywhere. It just makes your shop look very very unprofessional. If you can't have it translated perfectly, just leave it in English. I'm deleting this app as its embarrassing to have so many mistakes in foreign languages on your website. It's not fair to have people install this without knowing the translations are far from accurate. You have been warned!!

Quite easy install but it took some time (5-10 minutes) before the language selection drop down showed up, so I thought it wasn't working.
Once it showed up, I tried the one language I needed Swedish and it was quite a poor translation.
It was a nice that it was automatic, but google translate is not good at swedishEnglish translation.
Then, I couldn't go back to English which I thought would have stayed as the default language. oh well I probably could have gotten that back, but the swedish was too poor.
I deleted it after 20 minutes

Traduction can not be tuned and it's not professionnal traduction so not good enough (for me)
the style of the button is not nice (for my design)
No answer from the team in a correct delay

App failed to live up to expectations. It looks good but it could not recognise my site is completely in Spanish and the option for English would not appear in the list without clicking another language first then going back? I asked for it to be fixed and it was not..just being honest.