Nethereum is an open source .NET integration library for Ethereum. It is designed to help developers easily integrate the Ethereum blockchain into their .NET applications. It consists of modular libraries for features that are covered are writing smart contracts, cryptographic wallets, DApps, and managing blockchain data.

Infura is a DApp infrastructure provider that was created by ConsenSys and gives developers the tools to securely access Ethereum and IPFS. Their API enables users to set up Ethereum Nodes, and then install, configure, and maintain the Ethereum infrastructure more easily, and at lower cost. Infura was originally created by ConsenSys.

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.