Recs.
Updated
The Mavic Pro is the smallest drone currently being produced by DJI (the makers of the Phantom 4). It has a radius of over 4 miles, object avoidance technology, a 4K camera, and can fold down to the size of a bottle of water.
SpecsUpdate
Pros
Pro Smart safety features
When the battery is getting low, or the drone has lost contact with the controller, it will return to the starting point. It is also able to detect and avoid objects that you, the pilot, may not be aware of. Then, when you're done flying, the Mavic can land itself.
Pro Excellent lowlight
For a camera with as small an aperture as the Mavic has, it takes excellent lowlight shots. Here is an example.
Cons
Con Max 96fps in slow motion mode
The Mavic Pro can shoot at 96fps in slow motion mode, but that is not fast enough to catch something like a water balloon exploding in glorious fashion. In this example, things appear slower, but if you tried to slow it down even more in post-production the footage would become noisy and choppy.