Webviewer issue in Ipad | GetLayoutObjectAttribute

We have given the object name for webviwer for get some value from webviwer object

with the below calculation function working well in desktop application, that means we are getting some value from the url (which we have done in the php script.) via webviwer.

GetLayoutObjectAttribute ( objectName ; attributeName {; repetitionNumber ; portalRowNumber} )

but the same case not working properly When we go for Ipad.

Could anyone please share your comments if you met the problem before..

Note: This issue found only on fm 12 advanced.. bcoz we already done this same in fm 11 advanced