I have, Eleonora, and it's much like all these other online tools. OK but not as refined as things like Trados, which means that you work more slowly (i.e. effectively earn less money per project).
It also represents a dichotomy which I particularly dislike in that among developers/tool creators there seems to be a perception that we all live in cities and have wonderful 4G access. I live in the countryside and my connection speed is such that I'm lucky if I can do anything on the internet a lot of the time. Consequently a web-based tool is all but useless to me!