Loved this article about the design of Slack by Andrew Wilkinson of MetaLab:

Some highlights:

We did the logo, the marketing site, and the web and mobile apps, all in just six weeks from start to finish.

I felt the problem had already been solved. It was a crowded market and knew it would be difficult to make his product stand out from the crowd.

Most enterprise software looks like a cheap 70’s prom suit — muted blues and greys everywhere

It Feels Different

Throughout the entire product, everything seems to playfully jump around and pop off the screen.

Like a well-built home, great software focuses on giving its users hundreds of small, satisfying interactions.

In Slack, every piece of copy is seen as an opportunity to be playful.

With Slack, a bubbly, bright UI, delightful interactions, and hilarious copywriting come together to create a personality. A personality which has triggered something powerful in its users: they care about it. They want to share it with others. It feels like a favorite co-worker, not a tool or utility.