FaceCall is creates icons that can be used for speed dialing your contacts right from the iPhone's application launch (home) screen. Simply tapping these icons, as you would launch any application, calls one of your contact favorites.
Launching the FaceCall application itself prompts you to select a contact, then select the phone number you want associated with the icon that will be created. The app then uses Apple's Web Clips technology to create the icon that becomes your new one-touch speed dial. The picture you choose for the icon comes from either from the iPhone's camera or photo library.
One disadvantage to the icon creation is that, once the icon is made, you cannot tell which phone number from a contact with multiple numbers the icon represents. So, if a contact has a home, office, mobile or fax, for example you cannot tell which number is being dialed. It might help if the developers added letters to one corner of the icon, e.g. an "M" for mobile. As it stands now, you'll have a hard time creating multiple icons for a contact with multiple numbers.
The other disadvantage is that the use of Mobile Safari to create the icon isn't without issues. The 1.2 release states: "No more calls started by mistake from Safari" wasn't true in our tests. We found that when entering Safari later we often accidently speed dialed someone unintentionally. The app also requires access to Wuonm's server infrastructure while using Mobile Safari, potentially exposing your personal information albeit briefly in order to complete the process.
Finally the app is a victim of the iPhone OS' limited ability to manage home screen icons (no categorization, folders, etc.). You can create as many icons as you wish with FaceCall, but if you have a lot of apps on your, adding them to the mix makes things somewhat tedious.
Overall, FaceCall is one of the more useful speed dialers we've seen.