The iOS application does not support the document chaning feature. Document chaining works on the application via the Access Point and a browser as opposed ot the iOS application. This is because the iOS application is not the full Qlik engine so does not have the capability for chaining, whereas you are using the full engine via the browser. I have heard of instances in earlier versions where chaining worked, but it is not supported and in later versions does not work. I would recommend that you do not use it in iOS applications.