I do have all my cards stored in the cardstar app in my iphone but I keep the actual plastic cards in a passport holder.

I have a laptop backpack I have with me on EVERY trip I take and leave it in there. It has a pocket for my passport and some card slots at the side and I just put all my traveller cards in that along with a photocopy of my AAA and auto insurance card and also have a visa card from my credit union I only use for travel outside the US (no rewards but no foreign transaction fees which makes up for no rewards) and my ING atm card (has no fees so handy for travel). I figure if something happens that my wallet is lost or stolen I will have my passport in a different location for ID and will also have a backup credit card and an ATM to get emergency cash.