Since you using smart contracts it means you can make some good features on backend.
So, currently is football championship going in Russia, if teoreticaly Geo was had released app today would be a great feauture to attach national country flags to dropped coins.
E.g. one portugalian drop GeoCoin in Russia, but he want to attach portugalian flag to it to promote his country footbal team or something like that. I hope i could explain my idea properly. Or event atach any other images to each point like in agar.io. It would be very fun for all.
The idea is good, indeed.
However, there is a problem: you won't store the picture in the blockchain (even if it's the Ubiq blockchain, it doesn't matter). So maybe a link to a centralised server or something like this?
Maybe it would be easier to give the possibility to add a little text, so this portugalian can either write "Big up to portugalian football team" (or whatever he wants) or put a link of something, for example an image (of the flag, you got it).
I don't really know the technical limitations of this but since we can't store huge amounts of data in a blockchain, I think it would be a better idea.
PS: but you're right, it could be pretty funny.