Communication, project oversight, and task management are all integral to the success of any business. There are a lot of great options out there that each have their own advantages and disadvantages, but one of the most prevalent (and flexible) options is Slack.
Slack is, first and foremost, a dedicated platform for communication. In their own words, Slack "creates alignment and shared understanding across your team, making you more productive, less stressed, and just a little bit happier." We can't provide anything more than anecdotal evidence to corroborate that last bit, but Slack has definitely helped us to organize our office!