As far as I am aware, this was the second third-party application ever available for Palm WebOS (and Dali Clock was the third).
By default, the Tip Calculator only does whole numbers, because if you insist that your tip be accurate to the penny you are a cheapskate weirdo. Here in the Colonies, we use paper money, not coins. If your bill is $44.22, just enter $45. Don't go all Scrooge McAsperger's on us, ok? But, there is a "scrooge mode" that lets you calculate your tips so that no penny is left behind, if is how you roll.
Alternately, if you have the WebOS development kit you can just install it from the command line over USB by doing: