This GoPro Session mount can be used on almost anything. It has a flat base that can be mounted with zip ties or double sided tape. It is available in 20, 30, 40 or 50 degree angles!!
Adjustable Angle Bolt on GoPro Mount (All Neato Frames)
Adjustable Angle Bolt on GoPro Session Mount (Detroit Multirotor Frames)
Adjustable Angle Bolt-on GoPro Mount (Alien)
Adjustable Angle Bolt-on GoPro Mount (Martian II)