Photo Circle This is a free app where you can upload photos and share albums with friends. I have used this to take photos of my classroom set up and share it with other teachers. They also share their classroom setup photos with me so we can bounce ideas off of each other. Could easily be used to share photos of student work, photos of spirit week, etc.
Plickers A clicker but simplified. Free and easy to use tool that requires no electronic devices for your students. They can give their iPads a break! Instead, each students gets a unique barcode to answer with, a paper clicker if you will. A neat tool for teachers to use because it stores the data and responses of your students. Great for feedback and assessment.