I'm workin with:
Integer eMode

WebGet peMode of oWebApp to eMode
From WebAppConstants.pkg
// Responsive mode constants 
//  Note: It is important to keep them in order as this determines the rule  precedence (setting a tablet rule also applies to mobile unless  overridden on mobile)
    Define rmDesktop         for  10     // This is the default mode (i.e. desktop mode). This mode is not  normally explicitly used.
    Define rmTablet          for 20     // Default Tablet mode
    Define rmTabletLandscape for 21     // Tablet mode when in landscape orientation
    Define rmTabletPortrait  for 22     // Tablet mode when in portrait
    Define rmMobile          for 30     // Default Mobile mode
    Define rmMobileLandscape for 31     // Mobile mode when in landscape
    Define rmMobilePortrait  for 32     // Mobile mode when in portrait