Nxt is a blockchain platform developed by Jelurida, which is also developing the Ardor blockchain. Nxt's goal is to improve upon existing blockchain platforms with a modular toolset that enables users to create their own digital assets that can be listed on decentralized marketplaces. Nxt also features community driven voting mechanisms and has an architecture that separates the blockchain into parent and child blockchains.
The network is powered by the NXT token and has a Proof-of-Stake (PoS) consensus mechanism.

QuarkChain is building a blockchain with a focus on speed and scalability. They hope to significantly improve transaction times and reduce fees with an architecture that will rely on a two-layered blockchain and elastic sharding. QuarkChain uses a hybrid Proof-of-Work (PoW) consensus mechanism that is ASIC-resistant. Transactions are first confirmed on one blockchain layer, and then on the second. The network will be powered by the QKC coin.

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.