Cryptocurrency is indeed a truly revolutionary concept. But in order for it to stay popular and have the "hype" that it has now(along with artificial intelligence, machine learning and big data analysis), several years into the future, I believe that the blockchain technology should expand to other use cases other than just cryptocurrencies.
A lot of research is happening in this field right now and hopefully, many developers are coming up with newer and more innovative applications for the blockchain technology, while still incorporating the cryptocurrency aspect. For example, Ethereum, the blockchain network in which you can run decentralized apps, has its own cryptocurrency equivalent of bitcoin called ether.
There is a promising future for cryptocurrency and blockchain in general but developers should come up with innovative methods of implementing them.