Trading Cards has for years existed as a great activity on the ReadWriteThink site, and came out as an app last year. With this app, you can create a descriptive "trading card" about any of the following:
Each type of card has a different schema to it, and it actually would be a good pre-activity to have students predict what attributes would be on a card about a Real Place vs. say, an Object.
The website has a few extra choices of the type of card you can create, and also lets you create your own schema.
The app allows you to set up user profiles so that collections of cards are stored in the app. When creating a card, you can add a picture saved to the camera roll, access guiding questions and type text (limited to certain defined lengths), flip the card and finish your work, and save/print/email your card. As this is a task that may take several sessions, it's great that you can return to the app and continue work. On the Trading Cards activity on ReadWriteThink's website, you can download a partially completed card and re-open it later for continued work.
Trading Cards would be a great way to develop more advanced descriptive language while working with geography, books that students are reading or that you have chosen for the session, the Social Thinking® concept of people files, or other contexts.