The hand held cash interface

The interface on your iPod screen is, in default, no more complex than current screens in point of sale, it is just handheld, the size of a rock. Cash is still about counting denominations. In exchanges, person to person, the silicon is as good, in not better than gold. There will be less spillage of silicon than gold dust. But people generally have no need for precious metal piles.

So it feel just like hard cash, waking around with ATM cash on demand, from a prestored pile of it in your hand.   Under neath the simple, low IQ interface is the red/green warnings, like on confirm message at POS or cash back question, simple red/green. That model spreads across these simple enforceable contracts, the red/green warnings as the ledger exchanges have reliable meaning.

The user has a price risk vs transaction fee choices, insurance is better measured, meaning red/green works, is monotonic and bound. Outside the handheld are the secure applications and trade data from the pits. Voluntary contracts much easier to enforce with AppleID tech, we get a multiplicity of application over whelming hardware layer, which won't get smaller.