I'm afraid I'm going to need something like that very soon. I'm back playing with a pipe band (the same one that got me started playing pipes almost exactly 50 years ago, but that is another story). The horsehair sporrans have enough room for a credit card and a short letter. So the last event was a concert rather than a parade, so that I could have another sporran right there. I swapped that sporran for what I thought was a nice, fairly roomy brass cantle sporran with a soft leather bag. It turned out the phone caught on the inside of the cantle and cracked the screen cover. Parades end up somewhere different from the start, ergo the need for a non-traditional to carry the phone, wallet and keys.