You must have the LR Dashcam app to connect and communicate with the cam, adjust settings and view clips. Other apps will not work with it. To view clips, you can also just remove the SD card and read it in an adapter for any PC/Mac. It's good to get two SD cards, keeping one in the cam at all times. The SD card needs to be robust enough to handle constant use. I use a Samsung Pro Endurance 128GB SDXC Micro SD card.
The cam can sense movement when parked by either radar or g-force. You have the option to choose which one, or both and the sensitivity. Same for driving modes. As for light sensitivity, it's as good as any HD camera (is not 4K) without flash or infrared light assist. 99% of the time, mine is parked where there is sufficient ambient light.