Are you prepared to handle pictures that are inappropriate (non-weather) or even illegal (perhaps of military locations or underage) You can compare for example with the Strava app https://techcrunch.com/2018/01/28/strava-exposes-military-ba...
Going to Europe pictures could also make any picture with humans in them subject to GDPR requests and that may not be what you want either.
Thoughts?
"Recital 51 notes that photographs will qualify as biometric data only when they are processed “through a specific technical means allowing the unique identification or authentication of a natural person.”"
So Facebook trying to match your face to tag you in a photo counts, but the usage in this weather app doesn't appear to.
[1]: https://iapp.org/news/a/top-10-operational-impacts-of-the-gd...
Honestly I'd have to do some specific research and then probably contact a lawyer to have them do some research just to CYA (or rather, mine).
For the humans in pictures, definitely don't want that and would reject the photos. I'd rather reject many photos that contain the sky and have issues than accept all photos, since I think the training dataset should need on the order of ~5-10,000 photos. It should be achievable while rejecting any problematic photos.
HDPR is a major consideration for this project. I'm working to build in starting points like the ability to delete your data (coming soon) and also to download/export all data users send in.