Hey @leifeng
We will be launching our devnet this month, with testnet coming in Q1 2019, and mainnet in Q2 2019.
Follow us on harmony.one/twitter or our Telegram: https://t.me/harmony_one. Our latest newsletter is harmony.one/newsletter.
On product/development, see our thoughts on:
Sharding: Summary of Harmony's approach to sharding
Smart Contracts: Ideas towards a scalable smart contract architecture for a sharded blockchain
Networking: Inter-committee Routing in Sharded Blockchain
The competitive landscape is changing quickly right now so we are mostly heads down focused on developing our own platform while closely watching Ethereum 2.0, Zilliqa, and Dfinity.