Bearing in mind that JomGenius does not have full mobile device detection (just android, ipad, iphone, ipod), I think I'd structure it like this:

$is_mobile = $core_genius->check( "browser_type = ipod, iphone, ipad, android" );
$is_ie = $core_genius->check( "browser_type = ie" );
$is_ff = $core_genius->check( "browser_type = firefox" );

if ( MM_NOT_LOGGED_IN ) {
  if ( $is_mobile ) return AAA;
  if ( $is_ie ) return BBB;
  if ( $is_ff ) return CCC;
  return DDD; // any other device, for non-logged in (incl googlebot etc)
}
// from here on we know they are logged in:
if ( $is_mobile ) return EEE;
if ( $is_ie ) return FFF;
if ( $is_ff ) return GGG;
return HHH; // any other device, for logged-in users


Replace AAA-HHH with the relevant module ids that you want to use for those devices.

Cheers,
Stephen

That's why I like being able to configure MetaMod in PHP: it's relatively easy to structure any sort of rules like this and combine different conditions alone or in combination with others.