I am a big fan of the Yahoo weather app. I prefer this app more than the default iOS weather app. One of the core reasons for my attraction to this app is the beautiful location-based background pictures.
After some research, I was excited to know that those photographs are from real users, selected from a Flickr group and everyone has a chance to publish their photographs.
The challenge?
Till this point, everything sounds simple right? Here is a minor challenge: The photograph should have location information for Yahoo to associate it with a particular location, In other words, photographs should be geotagged.
At present, photos can be geotagged in Flickr itself using Organizer.
Here are the complete sets of guidelines: https://www.flickr.com/groups/projectweather/
Good luck to reach millions of smartphones :)