Every time you scan your vehicle, it will be automatically be documented within the app. That way, you can keep track of all the work that has been done on your vehicle.
You can also make custom logs to record anything done to your vehicle from getting your tires replaced, to getting gas. To do so, click "Add New Log" under the Logbook page. You will then be prompted through a series of questions regarding the log type, date, cost, and location. There is also a section for notes too.