Soundprism: Free. Great visualizer, great sound. Tried it today with 8 ipads at once.
Garageband: Love it.
Flipboard: Free. I get most of my information from flipboard. For some reason I didn't respond well to this when it first came out.
Keynote: $9.99. Been using this for developing presentations. Just have iPad version. Only rough thing is building photo library on iPad. Works very easily.
Show of Hands: Free. Fun diversion. Take a simple poll question and it shows you how each state has voted on the question and how age, gender, or party has different statistics. Great discussion opener.
AutoCAD WS: Free. This is very cool accompaniment to the very expensive CAD program. It works great. You can really manipulate the drawings with your fingers. Cool to play with.
Nota: 99 cents. Great music theory tool. Lots of drills and information.
Planetary: Free. Fun visualizer for your iPad music library.
Verbally: Free. Game changer for SPED students. Must have.
NPR: Free. Still the best. So much about music and arts. Can listen to all of their shows or find live stream.
Radio.com: Free. I use this when I'm working. Try to listen to different region, country, genre each day.
YouTube: "How do I do....." "Here check youTube."
Netflix: Free, with subscription. Last night I'm not feeling well. Cue up netflix and watch a movie in bed. Amazing. But they have a TON of content for schools! Check it out. Of course, its blocked in most places. Keep fighting!
TED: Free. They have added a search box. Works much better than before. Has all the talks.
Things I've had to give up:
NYTimes: This is tough. I used to read most of the paper. I just cant pay for it.