That's a zipper pocket with pleather and rivets for trim.
Inside is another zipper pocket on one side and a large divided slip pocket trimmed with outer fabric on the other side. It fastens with a magnetic snap.
The pattern called for sewing the pouch and lining together, then binding the seams on the inside with bias seam binding. Umm... I like Erin's method much better, with the seams ending up between the exterior and lining fabrics.
Incidentally, the zippered pockets are very small. They are about 5" wide by 3" deep. They're probably only good for car keys, chapsticks, etc. You'd have to have a very small cell phone to fit it in them.
I'm very pleased with how the bags turned out, even if it was a frustrating process. If you REALLY love them and decide to make your own, you can email me for details on how to work around the not-so-great pattern. By the way, I checked the pattern reviews for this seller. For the most part, they said things like "This pattern looks great - I can't wait to make it!" Not exactly a helpful review, is it? There was one, though, that said it all: "I got so confused I gave up." Now that's a more realistic review.
I'm off now to start another project, and this one I know will go well, because it's from a tested and much loved pattern by Erin, but one I haven't made before. I'll be showing you later......