I’ve seen many remote teams use Slack (or other group chat tools) for primary communication. It works well, if the team already has some experience with agile (i.e. they know what counts).
I experienced it also helps to establish simple protocols for Slack. For example:
- “we do not require everyone to read everything on the channel”
- “we tag daily standups with #standup”
- “we commit to giving our daily status between 8 and 10am”
- “if I have a question and need a decision, I tag it as #decision. Everyone has to either reply with #read or #veto (for yes or no) within a certain timeframe”
- “never address the whole channel with “@channel””
These are just examples — your protocols might be different. But it helps to establish a (simple) protocol like this.