In both my Betty Shopper bags I added a zippered pocket on the inside.
You just have to have one of these, for keys, phone, change, your bank card or for your earrings if you go swimming.
I have a very simple zippered pocket that I have been making for years copied after some winter jacket someone once had. I used to make these all the time when the boys were young and even more unreliable and I was waging my losing battles to get them to bring home notes from the teacher from school. Those guys couldn't ever make it from the school to the house without losing whatever important thing the school gave them. I had one efficient year when their sister was in the same school with the two of them but it went down hill after she went to junior high.
The same with rubber boots. First if I could get them to put them when it rained for a walk to school I was winning, but forget ever seeing those boots come home again. Maybe if I went hysterical someone would bring home two lefts, or between the two of them three lefts, but the names inside where always different, and not theirs. Reminds me of the summer they did swimming lessons and every towel in my house eventually disappeared. I read the riot act and told them to go to the lost and found at the pool and bring home at least ten towels, which they did. They were a bit indignant when even this didn't make me happy and said it was my own fault "You never told us it had to be ten of our own towels, we just picked the first ones in the pile."
I miss those days.
OK back to the pocket which I did perfect although no one ever used them, except me in a bag or in a jacket of my own so I wouldn't have to look for the keys in the grocery store parking lot.
First this is functional not decorative, part of the zipper tape is exposed, but that's what makes it so fast and easy, you can't have everything.
1. Cut out a pocket piece (I usually use a pattern envelope as my pattern, I always have one of those on hand).
2. Find a zipper (I didn't have a colour match for my pockets on hand, oh well) it actually is better if it is a bit longer, that way you don't have to sew around the slider and you can bend the end under.
3. Face the zipper down right sides together at the top of the pocket piece and stitch one side of the tape to the pocket. Flip it up and topstitch close to the zipper teeth so it won't catch.
4. Position the pocket on the lining and pin.
5. Fold under the ends of the zipper and top stitch the remaining side of the zipper directly on to the lining.
6. Fold under the edges of the pocket piece and top stitch the pocket in place.