I would recommend the application "Polish license plates" (with map)!
The application contains a list of all the Polish districts, along with the assigned license plate, the province and the capital district.
Some of the best features:
- Interactive map
- The full list of counties
- Sort by number, county, state and district capital
- Search by number, county, state and district capital
- The active development of applications (email me if you have questions, suggestions, comments)
- More soon!