Most still cameras are 5 megapixels or higher. Therefore, do not be fooled by the claims of HD for a camera when the manufacturer is relying on the resolution for still photos. It is true what they are saying but not the complete story. Having HD resolution for still images does not explain the possibility of also having a lower quality for video-image capture.
Many manufacturers mount cameras inside the body of the drone. This is acceptable for casual photography, but if you want more professional results, consider adding an external camera mount, or gimbal. Gimbals allow you to place your video or still camera in front of the drone body, away from the vibrating motor and rotors. Gimbals can swivel and pivot, providing you with additional control over your imagery.