IMO the killer blockchain app is voting. It makes use of the features that are unique to blockchain: censorship resistance, decentralization, and trustless transactions. I've been working on a paper for the last 6 months that details a system that makes use of crypto innovations like zk-snarks and some other novel technologies that lays a blueprint for how to use this tech to provide a voting system that would be beyond any central party's influence and would securely allow for voting from mobile devices and a host of other things that are beyond the capabilities of centralized tech - at least beyond the ability to be done in a manner that anyone would trust.
I've been watching the space since 2010 and can honestly say most projects are solutions in search of a problem.
I've been watching the space since 2010 and can honestly say most projects are solutions in search of a problem.