I have made a prototype that I plan on using for myself (new crochet bag) so the fabric is a bit daggy.
The bag will be 16 inches wide x 14 inches high with a depth of 5 inches. Inside the bag has 4 large pockets plus one small pocket that has insulation for a baby bottle or water bottle. On the outside of the bag there will be a zipper pocket big enough for you to place a mobile phone, keys etc.
At the moment I have some lovely large magnetic closures that I am planning on using so that you have easy access to the inside of the bag.
The strap for the bag will be 50 inches long but adjustable with padding for where the bag hangs on your shoulder. All bags will come with a matching nappy wallet and a change mat.
Would love to know your thoughts.