Question

what is the latest block chain development and top players with this tech, such as Digital Asset Holdings ?

Answer 1

The blockchain technology still has a few challenges to solve, it really depends what is important for you. Some projects have focus on performance like https://www.hyperledger.org/ other on privacy http://www.enigma.co/ others on business: http://www.r3cev.com/projects/

To understand blockchain well, you need to get down to the mechanism and understand the current issues with the decentralisation, performance, scalability, proof of work, reliability and privacy. for each of those points there are projects trying to solve. Here is a good intro: https://blog.plan99.net/the-resolution-of-the-bitcoin-experiment-dabb30201f7