As long as you are signing in with your same user credentials, you will connect to your Dash account on a new or different phone (or tablet.) We store your data securely in the cloud, so you're good to go.
Dash also works great if you have more than one vehicle – you can add more vehicles in the ‘My Garage’ menu. If your car model supports automatic VIN-decoding, then it will show up immediately as the car you are using. If you have an older model, like most produced from 1995-2000, you might need to input data or confirm manually.
Best of all, Dash will automatically switch between cars that report their VIN.