function _isAnySet(mData, vKey) {
		// are the vKey properties defined in the mData object
		var aKey = Array.isArray(vKey) ? vKey : [vKey];
		return aKey.filter(function (sKey) {
			return mData[sKey] !== null && mData[sKey] !== undefined;
		}).length;
	}
stop listening for changes in the app