Reading dollar amounts after "priced at" [duplicate]

This app is priced at three dollars and ninety-nine cents.

This app is priced at three dollars, ninety-nine cents.

This app is priced at three dollars, ninety-nine.

While the first usage will be the most widely accepted, any of the above would be an acceptable reading. People who use dollar currency, of course, may drop the currency name and read it as simply

This app is priced at three ninety-nine.

Incidentally, I'm not aware of anyone who represents the cents as a decimal for any of the major dollar currencies (i.e. never three point nine nine dollars or three and ninety-nine hundredths dollars or any such).