Identifying different denominations of dollar bills has long been a problem for the sight-impaired in the USA. A US $1 bill is the same size and shape as a $100 bill, making them hard to differentiate.
Many use techniques like folding different bills into different shapes, but this doesn't help when receiving change in a store. Looktel now has an app called Money Reader for the iPhone 4/3GS and fourth-generation iPod touch which will check bill
