Million Moments is a free Android app for creating digital picture books on your phone or tablet. To create a digital picture book you can upload pictures stored on your device, import images from Facebook, or take new pictures using the Million Moments app. After you have selected images you can add some text to them and arrange them in a Flipboard-like layout.
Million Moments could be a good way for students to create digital portfolios of the images that they capture on field trips. You could also have students create and share little digital picture books as a way to introduce themselves to you and their classmates.