Most people are fine with just a front-facing camera, but having multiple cameras gives you even more footage that can be useful in the event of a crash. Dual cameras: To record video of what’s behind (or inside) your vehicle as well as in front, some models include a second camera, in the form of either a small, separate camera that you mount to the car’s rear window or a second lens that points toward the car’s cabin and passengers.To draw power when the car isn’t running, a dash cam usually needs to be hardwired to the car’s fuse box, connected to an external battery, or plugged into the vehicle’s OBD-II diagnostic port. 24-hour monitoring: Most dash cams provide a parking mode (which records impacts or movement around your parked car), but it’s usually limited by the device’s field of view or power supply.The dash cam also shouldn’t share GPS data unless you specifically opt in to doing so in a connected app. A dash cam’s GPS receiver doesn’t provide turn-by-turn directions, though you need to use a smartphone car mount and mapping app or a dedicated car GPS navigator for that. The best models have the receiver integrated into the camera body or mount, rather than needing a separate plug-in device. GPS receiver: A GPS receiver lets a dash cam record a car’s location, the trip history, and the speed and direction of travel-all valuable information for figuring out how an incident occurred.The best apps also have a map that shows the car’s location, speed, and other details. Wi-Fi and smartphone app: We like an integrated Wi-Fi network because it allows the dash cam to connect to a compatible smartphone app, through which you can view, download, or share video.Sufficient field of view: We preferred models with an FOV in the range of 140 to 160 degrees-wide enough to take in a multi-lane highway or large intersection without creating a wide-angle effect that makes cars in front look farther away and details harder to see.Models without a display-generally not our preference-require you to use a phone or computer to view video footage and set up the camera. Easy-to-read display: Most dash cams have a display that’s 1½ to 3½ inches diagonal displays that are at least 2 inches make it easier for you to adjust settings on the fly and preview footage.Most dash cam makers give you a choice between mount types or sell other options separately. Mounts that attach to the windshield with adhesive pads are often more compact and very secure, but they can be difficult to remove for repositioning or swapping between vehicles. Generally we’ve found suction-cup mounts to be the easiest to use. Effective mounting system: We looked for mounts that held the camera securely yet allowed us to aim it easily, as well as to remove it easily.We also preferred models with buttons we could identify in the dark, as well as intuitive menus and a functional companion app. Easy-to-use controls: We looked for models with clearly labeled, easily reachable controls (especially the video-lock button).Night vision: We made night vision a requirement for a dash cam to be considered for testing since car crashes and other incidents you may want to document can occur at any time of day or night (as well as in dark environments such as highway tunnels).
We preferred models with 1296p or higher resolution, since their footage is often notably sharper than that of 1080p models, and we didn’t consider anything under 1080p.