Cal.com - Cal.com (formerly Calendso) is the open source Calendly alternative.
Dapp Store - DappStore is a platform, which lists all popular dApps
Dune Analytics - 675 million+ members | Manage your professional identity. Build and engage with your professional network. Access knowledge, insights and opportunities.
DappRadar - A list of the best decentralised Ethereum applications
Unidata - We all know that it is not that easy for web3 developers(especially for front-end) to access and present Web3 data due to the infrastructure design of blockchains.
AppScope - Appscope, one of the leading directories for Progressive Web Apps (PWAs).