Easy, simple to use. Quick meeting setup makes it easy to connect. The room url makes it easy to to keep standing meetings or to tell colleagues to meet me there. Joining meeting is easy and requires less software updates than other options. Only hosting the screen schare requires an install of a browser extension.
It would be nice if it offered a video option, but it's not really built for that. The controls aren't always easy to use. When you are in a screen share it's difficult to find the mute button in case of a cough or offline question. The controls are also not super intuitive.
If you are looking for a free, easy way to host online meetings and conference calls it's worth giving Uber a try. If you need video, look for another solution, but if you only need audio this will work great.
We use it to connect with clients and host meetings. We find that even those clients that have their own conference call solutions prefer to let us host because uberconference is so easy. Even the free level offers plenty of features to make it worth while.