Groestlcoin is a blockchain payment protocol with a number of technical innovations and an active developer community. Groestlcoin was the first coin that activated SegWit and supports the Lightning Network. Transaction fees are very low and it claims to have instant payments. It is also one of the only coins that can be sent over SMS.
Groestlcoin's active developer community has made the payment protocol very adaptable, and it a popular coin among many crypto investors. Groestlcoin has an ASIC resistant Proof-of-Work consensus mechanism.

Digix is digital gold on the blockchain. By combining the historical stability of a valuable physical asset with the advantages of a distributed ledger, Digix allows users to benefit from the advantages of both commodities and digital tokens.
Digix has an innovative Proof of Asset (PoA) protocol that allows it it tokenize a physical asset. The PoA protocol tracks an asset through its chain of custody, and enables anyone to verify its existence without an intermediary. Since every DGX = 1 Gram of gold, their platform can be used as a secure and transparent digital marketplace for gold.
Digix is also behind DigixDAO, a platform that allows users to contribute to building a blockchain-based digital gold payment system. They hope to create a decentralized autonomous organization (DAO) that will participate in creating this platform. Instead of issuing shares, the organization will be run by DigixDAO token holders.

ICON (ICX) is unique compared to most other digital currrencies. ICON's primary objective is to establish a unifying system to integrate an unlimited numbers of blockchains. This would allow numerous blockchains to work together and incorporate aspects of all of them. ICON is powered by a unique system called loopchain, that can adopt different features, rules, and consensus systems. The loopchain has different circles, with nodes that connect it. There are community nodes and individual nodes that are all connected to the ICON Republic, which is the entire ecosystem. These nodes can connect in countless ways and results in unlimited applications. The network has an innovative consensus mechanism called Delegated Proof-of-Contribution (DPoC).