A solid core
Ubuntu Touch comes pre-installed with a set of solid core apps that cover your daily needs. This includes everything you expect from a phone, like a dialer, contacts and calendar, but since it's Ubuntu, the OS comes with a fully-featured file browser and terminal (including essential command-line applications) as well.
Convergence in mind
Ubuntu Touch was created to converge the worlds of mobile- and desktop-computing, and that's also true for its applications. All apps are created with convergence in mind and can automatically adapt to screens from the smallest phone to the biggest tablet, and even work in window-mode on the desktop.
Dekko is a convergent e-mail client for Ubuntu Touch, that works with Gmail and Outlook accounts or any custom IMAP server.
Machines vs Machines - a free and open-source classic tower defense game exclusive on Ubuntu Touch
Find more apps on the OpenStore