[cdnsteve]

Cash still works when a city does not have power and ATM machines don't work. I've had a few instances of this in my life and I was caught without having much cash. Emergencies, cash still rules supreme.

The point about it getting lost is actually worse for a phone. You can also lose your smartphone. Losing your phone is a greater risk than losing the minimal amount of cash you carry on you. Think about it, if you don't have a password on your phone or you do and someone gets in, how much data are you exposing? Facebook, mass messaging all contacts, Banking, App stores, Email, the list goes on and on. Not to mention you're phones likely in a contract and you hold a few hundred dollar balance remaining on the item itself.

The problem with any technology is that even though we put our best foot forward, there will always be bugs and glitches. Cash, always, just works.