Do you use any app to document your spottings?

I usually take a picture whenever I see a foreign plate but I recently thought if there was a better way to manage that. For example, an app where I could upload/attach the picture, add the location, or simply some notes. And probably with the ability to sort them according to location, countries, or whatever filters you choose. Does anything like this exist?

Moreover, a legal question just to he sure if anyone knows. I live in Germany and from time to time I spot cool plates but until now idk if it's legal to share the photos here. Does anyone know if this is ok or forbidden?