Gapcoin is a new prime number based p2p cryptocurrency, which tries to eliminate the sticking points of other scientific currencies like Primecoin or Riecoin. It's a fork of Satoshi Nakamotos Bitcoin, a decentralized payment system which is independent of banks, governments and other centralized regulators. With Gapcoin, you will be able to anonymously send money around the globe in no time. The big improvement in comparison to Bitcoin is that instead of burning electricity for its own sake, Gapcoins Proof of Work function actually does useful work by searching for large prime gaps
DDK is a community platform that aims to create economic opportunities through the development of blockchain solutions. Since 2015, the DDK community claims to have contributed to a number of blockchain platforms.The DDK platform uses the Delegated Proof of Stake (DPoS) mechanism within its core. According to DDK, one of the advantages of a DPoS blockchain is that it depends on community members to participate in the maintenance and security of the platform so that each member’s participation provides benefit for all.