for her phone the pattern I've used is called Bare Essentials bag - I made one for a friend and one for myself to take to a quilt conference, but ... I teach school and have a 5th grader who wears a wireless heart monitor. She keeps leaving it places so I made a smaller version of this bag that she now wears everywhere. Makes me so happy everytime I see it. These sling across the chest - over the shoulder - so you hardly know you have it on. Has 2 pockets inside - for card or cash - and one pocket outside.
My phone fits in the outside pocket if that gives you an idea of the size. It's on my cutting board so you can see inches. It takes 1/2 yard and a fat quarter. The FQ makes the lining of the purse and of the pocket.
http://www.quiltingboard.com/picture...e-t201872.html