joinat is an application that will help you to organize small or big activities, you can easily create groups as well.
Repeating activities is also easy to create, just set the first date and then choose the repeating pattern and also set when you want the activity invitation to be sent out.
There are lots of features to simplify the handling of groups and activities
The joinat applications use is very wide, it fits everything from teams to individuals. For example: Sport teams, Hobby teams, Friends, Parties etc. Whatever event you are doing, joinat make the planning easy.