Here is some info about section access to create row level security
There is no out-of-the-box solution for object level secuirty, you may need to use extensions to "show/hide" objects depending on user profile loaded in the data model. check it on http://branch.qlik.com
First you should define your access pass in Excel sheet ( I mean, who wants access in data level, you should mention their UserID, UserName, Access, Field Name etc... for more understanding please refer below screen shot).
Once done, You need to load your section access file in the script between two keywords "Section Access" , "Section Application" .
Next you should map your section access file to your QVD.
(*Note: While applying section access, all characters are should be in capital letter. You can use "Upper or Capitalize" function) .
Once all done, you can load you script and publish. As per their restriction's, users will able to see application.