Much of what is reported as the huge growth in DeFi trading in the last half-year is because of UniSwap and the like, which are fundamentally only capable of operating on a single chain. Moreover, they have not only high explicit fees but high slippage (fees hidden as bad pricing that grows dramatically with transaction size). Such offerings also hide custody risk in wrapping non-native tokens. They do, however, offer convenient small purchases of tokens implemented on that same single chain but smart-contract gas prices are making even this use unattractive.
Some of the potentially relevant projects that we are aware of include: Etherdelta, IDEX, 0xExchange1, 0xExchange2, KyberNetwork, Newdex, Balancer, Uniswap, Sushiswap.