Hello Naser, I've had many students use this site to practice speaking English, especially with a native speaker.

(Survey) Answer: Yes, this app is very useful to find a language partner (free) or take a lesson (fee).

I've given an answer to your question, but as Tanja pointed out, the title should be "Survey", not "Servey".

Yes. Speaking a language is probably the hardest part of learning it and can only really be done well with someone else. Listening to a language is harder than reading a language, so practicing hearing it is vital. So, (in my opinion) once you have the real basics of a language, then having conversations in it is the best thing you can do to improve. It doesn't matter if you don't know the grammar that well, or if you're using the correct tenses. As long as you're speaking the language well enough to get our meaning across, and you're getting corrections as to how you should be saying things, it'll help more than any textbook. italki is based around talking with people who know the language you want to learn, and most of the teachers and tutors for a language will be native speakers. So yeah, I recommend it. There are some apps that are good for if you have five or ten minutes to practice some vocabulary or grammar on your own, but I'd take an hour with a native speaker over ten or twelve hours with something like Duolingo.