NSCoder Night is weekly event for iOS/OSX/Android developers where we discuss our projects and exchange ideas. For more than 4 years we has been meeting weekly at the cafe: RETRO Nørrebro in Jægersborggade. Between 1900 and 2300. It doesn't require sign up and is free.
CocoaHeads is big event every second month where there are presentations and topics. See the calendar for the next CocoaHeads meeting.