When the iPad first came out, the cover options were pretty weak. The official Apple case was nice because it was thin and bent so you could prop up the screen. I usually make zipper cases for devices, but for the iPad it seemed preferable to have a case that could stay on while you're using it. I was inspired by the Gigabyte Roll Pad that I use for my laptop to create this quilted case. It opens like a book to hold in one hand, or rolls open to prop up your iPad so you have a good viewing angle.
I tend to be a pretty reckless sewer, so I've factored in a lot of wiggle room. You could use more acrylic rods to thicken the roll and velcro is just one idea for the clasp. I've ripped out plenty of seams and redone them with no adverse affects on the final product. Have an iron on hand to keep things straight between steps.
Step 1: Supplies
I cut out all pieces much larger than the final dimensions. That way if the fabric shifts during construction, you have plenty of margin for error and can square it back up before binding.
* Outer fabric: 21" x 11.5"
* Lining fabric: 21" x 11.5"
* Batting: 21" x 11.5"
* Interfacing: 21" x 11.5"
You can use fusible or non-fusible interfacing
* Plenty of thread
The harness keeps your iPad in place with elastic bands. I use webbing so the elastic is secured to something a bit more rugged than cotton fabric.
* Interfacing or other thick, stiff fabric: 9.5" x 7.5"
I had to cut mine a little narrow because I only had a scrap left. That's ok.
* 1 inch webbing: 2 x 9.5", 2 x 5.5"
* 1/2 inch braided elastic: approximately 0.75 yards
* 14 (or a few more) 1/8-inch acrylic rods
* Binding fabric to match the outside of the case (or something complementary): binding should measure 4" x 70" (err on the side of longer)
* Velcro or another closing mechanism of your liking (not pictured)
* Sewing machine (I use a quilting foot, but it's not necessary)
* Straight pins
* Sewing needle
* (optional) Rotary cutter
* (optional) Rotary mat
* (optional) Masking tape