Penta is developing a blockchain platform that DApps can be built on. It will have a Dynamic Stake Consensus (DSC) algorithm to confirm transactions. The Penta network is currently powered by the Ethereum-based PNT token.

Celer Network is developing a layer-2 scaling platform that aims to enable fast and secure off-chain transactions and off-chain smart contracts. The Celer Network hopes to enable developers to create scalable DApps by increasing the off-chain functionalities of blockchains.

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.