The Matic Network is a sidechain based scaling solution for public blockchains. Matic aims to allow developers to better scale their Ethereum DApps by using a version of Plasma, along with side chains that use a PoS consensus mechanism. Matic plans on supporting other blockchains as well in order to facilitate interoperability.

ARK, which is a fork of Lisk, is developing an interconnected blockchain ecosystem that will make it easier for users to develop their own blockchains. Ark emphasizes interoperability and usability. Their moto is “Point.Click.Blockchain” and their goal is to allow for easy deployment of DApps. Ark's "push button blockchains" can be easily created with minimal programming knowledge. Ark also hopes to encourage adoption by developers by accommodating 18 different programming languages.
Ark has a delegated Proof-of-Stake (dPoS) consensus mechanism. Their governance model allows users to vote for delegates that secure the network. The top 51 delegates voluntarily share there tokens with their voters.
Ark contract execution service (ACES) connects ARK with other blockchains and will enable exchanges of value between them.

Stakenet is a blockchain with a unique Trustless Proof of Stake (TPoS) consensus mechanism that allows users to participate in the staking process without having to freeze their coins in the wallet. It's powered by the native coin XSN and is managed by its own masternodes. Stakenet (XSN) was created to build an ecosystem that allows easy and secure offline staking and cross chain communication. It has characteristics of Bitcoin, Dash and Peercoin, that were modified for their own purposes. XSN uses the Bitcoin Core, an improved Dash masternode architecture, and Peercoin's validation mechanism for creating new blocks.