DNG is Adobe's proprietary RAW format. When I shoot RAW on my Nikon it's a NEF file.... every company has their own proprietary version. DJI adapted the DNG format probably because it was easier than programming their own version and getting software companies to adapt to another format.
DNG will open and perform best in an Adobe software program (Lightroom, Photoshop, etc) because that software is designed to manipulate that file, but Aperture should be able to open it with a plug-in. I don't use Aperture myself because Adobe's software is so powerful so I can't offer instructions on doing so.....
Lightroom is the best "bang for your buck" way to edit. The software isn't very expensive and the DNG file will give much more bit depth and dynamic range to edit from. Adobe also recently provided an update that gives the lens correction for the DJI Phantom so it removes the distortion and warping from that fisheye lens.
Kristen