Slack

I love Slack's ease of use and simplicity. New users can get up to speed quickly and begin using fun features like @mentionds, /gifs and :emojis: The file attachments and search speed are well done.
Slack's real power is in all the integrations, so I love being able to hook up a dozen or so apps and collect all my notifications in one place. Also, the freelancer community has embraced Slack because of their free/cheap plans, so it's very convenient to keep in touch with a variety of contractors by just inviting them (since most already have their own Slack plans).

Slack isn't great at providing structure to your work-life. The #channel structure does aid in some structure, but Slack's support for threads is awful--they don't make any sense, and most people can't figure out how to use them. These deficits are offset somewhat by searchability, but for the most part you'll just be scrolling through endless conversations if you want to find a particular piece of info.

I like the ability to stay in touch with our users via whatever device I'm currently using. For example, I can respond from my home computer, tablet, work computer or via my phone.

I especially like the ability to be notified of a new message via my phone where I can read the message on the phone but can step over to my laptop to reply.

I also appreciate the ability to add an email thread to a Slack Channel by simply adding a slack email address (each channel has a unique email address) to the CC field when I reply.

The biggest con for me is the extremely limited amount of formatting available to Slack messages. I can make a font bold and add links to files/images but I really miss the rich text features many similar apps provide.

It's also frustrating to need to keep typing adding the user name(s) when I'm responding to a message. I'm assuming that this is by design but it would really be nice to be able to "Reply All" to a conversation thread.

The desktop Slack application (running on Windows 10 Pro) has a "clunky" feel to it. It's written with a framework that allows the Slack developers to write HTML and JavaScript code that is essentially compiled into a Windows application and it definitely shows. Something as simple as selecting text is counter-intuitive (until you realize that it's essentially a web page mascaraing as a Windows application.

The great thing about Slack is, first of all, it has multiple pricing plans. Especially, the fact that its first pricing plan is completely free. So it is great for anyone who is just starting a team, whether it be for a start-up for either a non-profit or a business. You have the ability to share files, communicate in real-time, receive real-time notifications, and communicate with multiple people at once. As well as do some small project management functions.

The only shortcomings I would say Slack has, is the fact that they are obviously a software that is mainly built for the purposes of communication between people in real-time. More like a glorified messenger app. So the file sharing, collaboration, and other project management features leave somethings to be desired.