I tried the same thing on a VA (works great in the sim - but in the sim, there is no watch face so can't test it)
On The VA, when i do a return true for the OnHold, apparently it will still go to the watch face.
Is there some secret to disabling or diverting the default behaviour? something besides Return True?
function onHold(evt) {
var keynum = Lang.format("$1$", [evt.getType()]);
Sys.println("onKeyPressed keynum:" + keynum);
return true;
}