We are trying to find another tool to replace groups.io but then I stumbled on this group discussing a mobile app version of groups.io.
How interesting!
I have spent the last week researching existing apps to meet a "generic" club's needs and if it was feasible to design an app for specific groups. There are a number of apps used by clubs and sport teams that might more efficiently replace GIO for some. I have found apps that integrate messages, calendars, membership lists, surveys, etc for 200-500 members. This would effectively replace the "mailing list" use of a basic group with over 100 members but at a lessor cost ranging from $30-80 a year. I sent some feelers out yesterday to the more promising apps.