I joined MemRise in 2013 and have been very active on the web ever since. I now also use the Android App concurrently.
On MemRise I have created, supported (as a Contributor) or looked after (Curator or Custodian) abandoned courses in a wide range of subjects but mainly on three themes.
The web link above shows my interests and those courses.
I have contributed to all the ‘old’ Forums including making suggestions for enhancements and supporting others, and I have been contributing here since May 2016.