I recently found this awesome app Zombies, Run! It has an accelerometer so I needed some way to attach it to my arm. This is what I came up with.
Cotton yarn - DK or light worsted
4.5 mm hook (can be swapped for a 5.0 mm hook)
Chain the length of the bottom of your phone, mine was 11 ch. Each phone is a different size so it does not matter how many ch's you end up with as we will be working off measurements. So although my pattern will say 11 ch just insert your number into the pattern.
Round 1: Ch 11, sc in the 2nd ch from the hook, sc in each chain across. Place 2 more sc into the last ch. Now working on the opposite side of the ch. Sc in each stitch across. Place 2 more sc into the same sp as the first sc you started with.
(you will have 3 sc in each end. So for my pattern I should have 22 sc at the end.)
DO NOT JOIN ROUNDS. MARK START OF EACH ROUND WITH A STITCH MARKER
You will find that along with each phone being a different width they are also a different height so I cannot give you an exact number of rows for your phone. Continue to sc around until you reach the height you desire. Mine has 16 rows. Finish off.
To make button strap for the case:
Find the middle of your case and attach yarn 2 stitches to the right.
Row 1: Ch 1, sc into the same st as ch 1 and in next 3 st. (4 sc)
Row 2-7: Ch 1, turn. Sc into the same st as ch 1 and in next 3 st (4 sc)
To make button loop, ch 1, turn. Sc into same st as ch 1, ch 3, sc into last st. Finish off.
To make strap to go around arm:
Row 1: ch 11, hdc into the 3rd ch from the hook and in each ch across. (10 hdc)
Row 2-30: ch 2, hdc in each st across. (10 hdc)
Please note you can adjust the rows to suit your arm measurement but remember it will stretch. I find it easy enough to move the button though.
Sew button onto front of case and also one to the opposite side to the button loop on the strap that goes around your arm. You may need to adjust the button after a while as it is bound to stretch.