I was surprised that Evernote was not listed. I had to go back and double check to be sure I hadn't missed it. I tried Evernote on and off for about a year before I really gave in to it. I mean that I started keeping absolutely everything there. You can save documents, of course, but also pictures and webpages, just everything you need. It is such a great place to organize your work and private life. I keep all of my lesson plans there and can pull them up on a mobile device or on any computer attached to the web. I do pay for the premium service. I think it is well worth the price.
I love the app, Chirp. I haven't used it except for fun in social situations, but I can see it being very useful in classes that have/use iPads or iPhones. Chirp will send what ever is on your device to every device in the room, or within hearing distance. It emits a high pitched sound when sending out the page or photo or whatever you are sharing.
I really enjoy YoWindow for weather. It has a picture and shows the wind or rain or whatever is going on. As you run your finger across the screen, the photo changes from day to night and shows the changing weather. Oh great, looking at this app I see that it is supposed to snow most of the day on Monday starting at 6 am. Another wonderful drive time.