Twitter: https://twitter.com/tezos
Tezos Announcements (Telegram): https://t.me/TezosAnnouncements
Tezos (Telegram): https://t.me/tezosplatform
Tezos Developer (Telegram): https://t.me/TezosDevelopers
SmartPy (Telegram) : https://t.me/SmartPy_io
Baking Bad (Telegram): https://t.me/baking_bad_chat
Tezos-dev (Slack): https://tezos-dev.slack.com/ssb/redirect
Tezos-baking (Slack) - Needs to be requested, do reach out.
MadFish/Temple (Telegram): https://t.me/madfishdev
Kukai Wallet (Telegram): https://t.me/KukaiWallet
AirGap (Telegram): https://t.me/AirGap