Valve released a Steam app for smartphones, that people have been asking to be released for a while.
The app's a pretty simple app. It gives users access to their friends list to chat, access to the Steam store and Steam news as well as account settings, too.
The layout is pretty nice. It's kind of like the Facebook app layout. With the menu on the left hand side, and the friend's list looks quite similar to the Facebook Messenger app layout.
As Valve are wanting to focus on gaming in the smartphone market, this app will most likely expand for access to smartphone games in the future, but it's useful now for people who want access to their Steam account to purchase games on-the-go, especially during the Steam sales.