A license is only necessary for drones of >5kg.
The basic rules for Mavic are:
- no higher than 100m
- not at night
- always in VLOS
- not over sensible areas, like crime scenes or accidants, power plants, industrial areas, highways (Autobahn), crowd gatherings, national parks, national reserves, 1.5km (1mile) around airports, private property...
- liability insurance necessary
If you want to publish your photos/videos or plan on using your drone for commercial reasons, even more restrictions apply!
Of course, most of those rules aren't enforced (yet) as long nobody feels disturbed and nothing bad happens
From October there will be a plaque required with owner information.