Expedia's mobile Web site has made several modifications to the desktop version of their hotel booking form: the layout has been optimized for slender mobile screens; the "search near" set of options has been listed out; and the room count input uses a set of "+" and "-" buttons instead of a drop-down menu for input. Yet, there's still room for improvement.
- The form uses a free-form text input field that requires users to provide clarifying information on another screen if a mistake is made. And in many mobile contexts (fat fingers, one-handed typing, on the go) —mistakes do happen.
- The date selection field makes use of a calendar pop-up that requires people to tap a small ">>" target to advance to the previous or next month.
- The set of inputs for guest count uses (up to) three drop-down select menus for input, which require manipulating a list of options in a pop-up list.
Kayak's mobile iPhone application also allows people to book hotels but it features a few additional mobile optimizations.
- Current location is available as a single click input in addition to a free-form text input. This allows people to search for hotels where they are now without typing.
- The free-form text entry field provides inline suggestions as you type. This not only reduces the amount of typing required (it only took me 3 characters to see Monterrey, CA), but it reduces errors as well. On the Kayak form, there's little need for the clarification screen Expedia requires.
- The date selection calendar allows people to use a simple scroll gesture to move between months instead of tapping a small target to change months. Users can just flick the calendar itself up or down through direct manipulation instead of having to use the ">>" control Expedia requires.
- The Kayak form doesn't use any drop-down menus, opting instead for "+" and "-" buttons that are easily tapped on a touch screen. (I'm not sure why Expedia uses these for room count but not guest count as both inputs only need to support a small number of possible values.)
In aggregate, these small enhancements go a long way to making forms on mobile devices faster and easier for people to complete.