Someone ought to… I will

How often are we in some public place, and notice a major deficiency? Like when there is a muddy path instead of a sidewalk, or where some railing at a dangerous ledge would be a good idea, or even just where a playground might be nice to have? If someone is walking with us, how often do we tell them „Someone ought to…“ or „When will the government get around to...“? And that is the end of it. What if there were an app for that, that let you instead say „I will change this“?

What is needed is a mobile application that can immediately be used to jot down the idea and attach it to that geographic location. Other users of the app can elect to have alerts displayed when they walk in to an area with ideas, check manually when they are at the same place having the same idea, or even just from their home scan for ideas in their local community, and then if someone else‘s ideas interest them, they can follow that idea, contribute suggestions, and when a critical mass of interest is attained, create through the app an Ethereum smart contract to arrange funding, volunteer hours, designate some trusted third party to audit the funds, etc.

I don't know-- does Ethereum support some sort of database?  Maybe there is some other blockchain for that?  Ideally there wouldn't need to be one server somewhere.