Bezel swipes are a clever way to activate functions without having to add physical buttons (as on the iPad) or persistent software buttons (as in Honeycomb). But they have their drawbacks. If you are careless, it's easy to activate capacitive bezel elements unintentionally. On the PlayBook, for example, there is a Fruit Ninja-style game called Popcorn Rush that relies on swift swiping. However, Orville Redenbacher himself would find it difficult to pop the airborne snacks without activating the app switching mode on the PlayBook. Talk about a kernel panic.
Capacitive bezel controls can cause problems on other devices as well. On the Samsung Focus, for example, if your fingers stray as you are zooming out a map using multitouch, it's not difficult to hit one of the three Windows Phone keys that will take you away -- if only temporarily -- from your current app. Again, this accidental activation becomes even easier in a game that requires fast zooming or swiping that could inadvertently extend beyond the display area.
The bezel certainly isn't the first control to have issues with accidental activation. Many notebook users bemoan the sensitivity of trackpads and companies have responded with features such as sensitivity adjustments, palm detection, and the ability to turn off the trackpad completely. And Windows gamers once had a formidable foe in the Windows key. But while a mouse offers an escape for those who suffer from a twitchy trackpad, touch has simply become too integral to the operation of tablets and in increasingly all handsets.
In the case of the Focus, it seems like a pretty simple fix. Just make sure that a capacitive button activation requires a small gap in time between a swipe toward the "bottom" of the screen and capacitive button activation. For the swipe issue on tablets, there could be a few alternatives. If there are alternative navigation methods such as on the TouchPad, there could be an option to disable bezel gestures, at least for certain apps such as games. For devices that depend on bezel swipes, there could be an option to require a two-finger swipe to activate the function. Whatever the case, the chosen alternative has the opportunity to preserve the slickness of the feature while avoiding any surprises.
Ross Rubin (@rossrubin) is executive director of industry analysis for consumer technology at market research and analysis firm The NPD Group. Views expressed in Switched On are his own.