The ability for users to send messages back and forth with each other. It's easy to use, it has some great features like scheduling meetings or reminders. I wish there were more options when sending images as well. There isn't an option in the app itself that you can add your own pictures which makes things difficult if you are trying to share something from another website. If someone needs help right away they will find this useful. We have been able to communicate quickly between our team members without having to email them individually.