I'd recommend Slack, JIRA, and daily stand-up calls. Slack is good for general news and messaging people on your team. Daily stand-ups and JIRA are nice for issue tracking, planning, and making sure everyone is on track.
To build on that, encourage everyone to get in the habit of using email and Slack instead of talking (Those who aren't currently remote.) For example if someone has some feedback on some code, they should post it in your code review platform or Slack, not lean over and discuss it with their coworker in person.
I'd actually avoid daily stand ups assuming a distributed team. Focus on async communication that has a written record.
What's great about Slack too is that you can create additional channels to split up discussion into different broad areas or concerns.