I saw your scarf, it's awesome! That's next on my list. I didn't follow a pattern for this actually. I think it'd be pretty easy for you to do it on your own for your iPhone too. Just measure your phone, figure out what your gauge is, and multiply the number of stitches per inch times double the width of the phone (if you knit it in the round), and you've got the number of stitches you need to cast on! I used the gauge specified on the yarn, which was 17 stitches in 4 inches: so that's 4.25 stitches per inch, times the width of my Kindle, and I ended up with 42 stitches. Then just try it on as you go along until the piece is long enough to fit your phone. I hope that made sense!