The app shows UK vehicle information, tax prices and MOT history by registration number. It shows the information all on one page.
The vehicle information comes from the DVLA (Driver & Vehicle Licensing Agency) Vehicle Enquiry Service. The MOT history comes from the DVSA (Driver & Vehicle Standards Agency) Vehicle MOT History Service. The tax prices come from the DVLA Rates of vehicle tax PDFs.
Using the app saves you doing three separate searches on the Government sites.
When you make a search on the app the DVLA and DVSA servers are queried, if data is returned it is displayed. The tax prices are determined by the vehicle data returned, year of manufacture, year of registration, CO2 emissions etc.
You can search for vehicle information for cars, vans, bikes, trikes, trucks, buses, any vehicle with a registration number. MOT history is only shown for cars, vans, bikes, trikes (Classes 1,2,3,4,5,7) as this is all that is returned from the DVSA server.
The vehicle information shows such things as the tax and MOT status of the vehicle which tells you if it's taxed or MOT'd or not.
Tax prices (otherwise known as Road Tax or Vehicle Excise Duty) are determined from the returned vehicle data and should be quite reliable (providing the information returned is correct). Where it is not possible to determine the price, this is stated.
A vehicle has to have an annual MOT test when it reaches three years old (from the date of registration). If the MOT history search doesn't return any information, it may be because the vehicle is less then three years old and hasn't had its first MOT. Only tests from 2005 on are provided.
The app shows your search history so you can quickly go back to a previous search. You can also save searches for easy access later.
The app uses Government information under the Open Government Licence V3. As stated above, the information comes from the Driver & Vehicle Licensing Agency, and the Driver & Vehicle Standards Agency. The developers do not represent any Government entity, including the DVLA and DVSA.