Works with CiviCRM 4.7 and should work on CiviCRM 5.0 or higher
This extensions shows a new field on the contact summary tab which shows either the first activity of the contact or the first group membership.
Screenshot (click to enlarge)
Releases
Since CiviCRM 5.x, extension releases compatible with CiviCRM 5.0 are compatible with 5.0 and later. An extension release compatible with 5.25, for example, means that it requires CiviCRM 5.25 or later.