Around 2.5 million ETH (approximately $400 million) is locked in decentralized applications. The dominant dApp is MakerDAO DAI smart contract, as it has around 2.2 million ETH. The second runner-up is Ethereum Name Service (ENS). In June 2017, it had about half a billion ETH. Right now, it is around $2 million, which means that individuals can create a ETH address using trust nodes.
The third strongest performer is Compound, a dApp that permits users to borrow and gain interest through lending ETH and other tokens. Compound has around 40,000 ETH and its overall assets are $27.5 million. Behind Compound is Uniswap, whose usage is growing. It as about 30,000 ETH as well. Following is Kyber.
Dai launched at the start of 2018 and people are waiting to see how the system performs. There is also a protocol level taking place concerning proof of stake testnet, which according to Vitalik Buterin, will provide an interest rate of 2% to 6%.