"Teşekkürler. Hoşça kalın!"
Google Translate is quite useful for me, but I might not use it for what others use it for. I have no idea how one would use it for language learning, so I certainly don't see it as a rival for Duolingo or other programs like that. It also often does not take into account syntax, so the English translation of a non-English sentence will often be a sort of jumble of words. It also sometimes has difficulty with grammatical endings, especially of agglutinative languages like Turkish. However, I find that it usually does pretty well in giving a direct, word for word, overly literal translation. What it produces is often nonsense, but if you have some sense of how the original language's grammar works, it is often quite understandable. That, I find, is one of the uses of a course like Duolingo. Just from the Duolingo course, for instance, I could not read an article in Hürriyet. The nonsense that Google Translate produces from such an article, though, has a Turkish form I am now familiar with from these lessons. I find the more familiar I am with a language, the more Google Translate's translations from it become useful to me.