They should start making dashcams that are also cellphones (or vice versa). Cellphones already come with both forward and rear cameras. A simple mount could be glued to the dash; the mount would have a pin that would activate 'dashcam' mode which would start both cameras. If needed you could plug in a charge cord after mounting the device on the dash. Likely you would remember to take it with you when you park the car since it is sitting right up there on the dash, and it is *your cellphone*.
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