The "Download Now" link directs you to the iTunes App Store, where you must continue the download process. You must have iTunes installed in order to open the link, and you must have an active iTunes account to download the application. This download may not be available in some countries.
Good service deserves a good tip. So why not use a foolproof method of deciding your Tip. TipClock does just that, sure it can calculate a tip, but more importantly by using the TipClock Demerit System or TipClock System you can be assured your tip matches the service provided. Swiping your finger across the iPad or iPhone issues a tip Demerit for poor service or adds a point for good service.