  Blockchain technology has attracted tremendous attention in both academia and
capital market. However, overwhelming speculations on thousands of available
cryptocurrencies and numerous initial coin offering (ICO) scams have also
brought notorious debates on this emerging technology. This paper traces the
development of blockchain systems to reveal the importance of decentralized
applications (dApps) and the future value of blockchain. We survey the
state-of-the-art dApps and discuss the direction of blockchain development to
fulfill the desirable characteristics of dApps. The readers will gain an
overview of dApp research and get familiar with recent developments in the
blockchain.
