Communication is key when working remote.
You can't walk by a co-worker and start a conversation anymore. (and disrupt them too… rude, right?)
With a myriad of options, it's important to be crystal clear which tools your organization uses and for what purpose.
That's what I call “The Communication Pyramid” (although I doubt that I coined the term).
Let's break it down (by flipping the pyramid and start from bottom to top):
1. The asynchronous basement
The virtual hub of your organization. Announcements, ideas, feedback, updates, and everything in between. Could be a forum (I highly suggest that) or a messaging app used right (hard mode).
2. Asynchronous In-Context Comments
Every Comment on a Google Doc, every Pull Request on GitHub or comment in your Project Management Tool is also asynchronous communication.
3. Synchronous Video Chat
Your 1:1 meetings, town halls, unplanned meetings to discuss very complex issues (don't forget to write meeting notes!).
I recommend a tool with permanent voice/video channels like Discord here. It creates a feeling of “entering the tribe” and belonging.
For instance, I like handing around in a channel when I do light work.
4. Seeing each other in-person
To truly bond with each other, in-person sessions are still the best option. Annual company retreats, team events or conferences.
There are many variants to choose from. I recommend at least two per year.
5. When things go south, pick up the phone
Finally, in case of an emergency, it is still a valid option to pick up the phone and call a pear. Make sure its really necessary.
It's not that important what tool you pick, but it's important to document it well. Which tool for what purpose.