The iPhone Photography School has many informative videos on YouTube.com.
Found this video especially helpful! Got some sweet fireworks photos on the 4th!
Plus he is sooo calm.

How many do you know?
1 Swipe left to open camera app
2 Set focus yourself
3 Adjust exposure manually
4 Lock focus & exposure
5 Use burst mode
6 Take photos with volume buttons
7 Take photos with headphones