Use Popplet to make a mind-map to help you introduce your hometown or your vacation highlights, or use it to help you present your research project topics. This can be useful for teaching your partners key vocabulary, asking your discussion questions, and presenting your opinions.
The one above is one I made just to test the site. The one below was in the public gallery. It’s pretty amazing:
You have to sign up, but there’s a free account that allows you to make 5 Popplets. You can choose to collaborate on one Popplet, too:
There’s an iOS app (lite for free, paid is ¥450). I don’t see one for Android, but that may change soon.