Top 5 Decentralized Cryptocurrency exchanges

IDEX
IDEX is an Ethereum-based decentralized exchange that features Ethereum and ERC20 token trading pairs. Like EtherDelta, it employs smart contracts that allow users to manage their private keys and trade in a secure, peer-to-peer environment. It also features Ledger Nano S and Meta Mask Wallet integrations, safer alternatives for fund management than manually entering your private key.

Wave
Waves' decentralised exchange (DEX) allows users to trade Bitcoin, Ether, Litecoin, ZCash and other cryptocurrencies, as well as fiat currencies such as USD, EURO and TRY. Trading is as fast as on a centralised exchange, but users retain complete control over their funds at all times. Trading fees on the DEX are low and fixed.

CryptoBridge DEX
CryptoBridge is a decentralized exchange (DEX) that supports trading of most popular altcoins.

In addition, another unique selling point is the usage of a multi-signature federated gateway software used by a dozen trusted gateways, operating on multiple continents, enabling trust-reduced issuing and withdrawing of the supported coins.

This exchange has a native token called BridgeCoin (BCO) which has token stake and 50% revenue sharing with BCO holders.

Bisq (aka Bitsquare)
A peer to peer marketplace and a fully decentralized exchange requires no name, email, or ID verification. It uses Tor and doesn’t hold fiat or coins on their servers.

ForkDelta
ForkDelta is a decentralized exchange that lets you trade Ether and Ethereum-based tokens directly with other users. It doesn't rely on a centralized party to store user's funds and facilitate trades. Trades on such exchanges occur directly between users using the same smart contract.