Chromia is a relational blockchain platform that is designed to be both a blockchain and a relational database. Chromia was created by a Swedish development company called ChromaWay, with the intention of combining the advantages of a blockchain's transparency with the benefits of a relational database system, such as data independence and reduced redundancy.

The Interplanetary File System (IPFS) is a decentralized network protocol for sharing hypermedia in a distributed file system. IPFS can be used to link blockchain transactions This effectively timestamps and secures the content, without having to put the data on the chain itself. Filecoin, an IPFS-based decentralized storage cloud, is closely related with the IPFS protocol, and provides the incentive system.

Ignis is a blockchain platform that is being developed by Jeluirda; the company behind Ardor and Nxt. Ignis is a child chain of the Nxt blockchain. Jelurida is developing blockchain platforms that will enable users to develop decentralized applications, and will be based on a parent and child chain architecture.
Ignis allows users to create child chains with specific features and to create tokens that meet their needs. This project is closely related to Ardor and Nxt.