The principles described herein provide methods and systems of providing a user interface to allow a user to compose and send an electronic communication quickly and conveniently. For example, a user interface includes split-pane interface having a navigable tray area and a composition area. The navigable tray area may include categories of trays, each tray including a navigable listing of content items that may form part of the electronic communication. The navigable tray area allows the user to navigate from one tray to the next to access different types of content items to be used in composing the electronic communication. When composing an electronic communication, a user can select an item in a tray, and the item is previewed in the composition area and can become part of the electronic communication.