Ubiq is an Ethereum fork that aims to create a more stable smart contract platform for building DApps. Ubiq's protocol currently uses a Proof-of-Work (PoW) consensus mechanism, but will switch to Proof-of-Stake in 2019. The network is powered by the UBQ coin.
Ubiq's goal is to create a reliable and stable platform for developing DApps by modifying Ethereum's code base with important changes that will make it more secure and reduce instability. Consensus is based on their Flux Difficulty Algorithm, which is designed to constantly adjust the hash rate to protect against network attacks.

IOST (Internet of Services Token) is a blockchain platform that is focused on improving transaction speed and scalability. IOST has a unique Proof of Believability consensus mechanism that is based on past contributions and behavior.
The company claims that their platform will increase security and efficiency compared to other platforms. IOST uses a sharding technique that splits the network into smaller ones and randomly assigns tasks for the nodes on the network.

Lisk is a blockchain-based platform that allows developers to build and publish their own applications. Lisk uses sidechain development kits, that are written in Javascript, to enable users to create their own blockchain applications according to their needs. Each decentralized App runs on its own sidechain that can be customized, and is connected to the Lisk blockchain, which has a Delegated Proof-of-Stake (dPoS) consensus mechanism. The Lisk network is powered by the LSK coin.