So, this is the motif I made for the bag's front.....
Back view - you can see the outside pocket. If I made another bag, I would divide the outside pocket like Larissa said to do for the inside one. It would not gape at all, which it does now (a little).
Inside, there is a 2nd pocket which is very useful.
Larissa said to stitch the flap on the outside of the bag, but I did not fancy this, so I rather added the flap (& strap ends) between the layers, stitched the lining to the main bag all the way around, leaving a gap down one side of the lining to turn the lining back into the bag. Then I pushed the lining through that gap & stitched the gap up. Also, I made the strap adjustable by using D-Rings on each side to attach the strap & a slider on the strap. Now the strap can be shortened to wear on the shoulder as well.
I loved this pattern & the proportions are great!
Go on... give it a try - this is a really easy pattern & it works very well.