Slack is an easy-to-use messaging service and integrates with popular services such as Twitter and Dropbox. Conversations or channels are organised by topic of which you can have as many as you like. The design is slick and simple, and you can share any file type (including photos and videos) with colleagues in a fraction of the time it would take to email them. It also has video call functionality for up to 15 participants, for those days when you need to see your fellow workers’ faces.
