[This review is based on experience from the Spanish section of the game]
I feel like the gameplay is rough on the edges and could use some work. Finding the people who are going to speak with me are just a little bit too far away to ensure perfect engagement to the game.
One thing I'd like to see out of this game in the future is for some kind of story based element to it. Think of it like this - you are lost in the city and find someone willing to take you in to help you around and get your footing in communicating with the locals. They bring you in and treat you as their own while showing you various items and telling you what they mean as well as connections to other things and verb conjugations.
Think of a section in the living room of a house where the guy shows you his family and runs down the various verb conjugations for, say, hablar, using you and his family and people-props to demonstrate.
This has lots of potential, keep at it!