i found how to create RTL mobile theme. here are the steps (for version 2.80) -
1. download jQuery Mobile RTL from - http://www.intlaqa.com/jquery-mobile-rtl/rtl.jquery.mobile-1.3.0.zip
2. files- rtl.jquery.mobile-1.3.0.js rtl.jquery.mobile-1.3.0.min.js should be copied from the ZIP to folder : \Scripts
3. files- rtl.jquery.mobile-1.3.0.css rtl.jquery.mobile-1.3.0.min.css should be copied from the ZIP to folder : \XXX\Themes\XXX_Mobile\Content ( i assume you create a new custom theme for mobile like you should do on the desktop version)
4. files - Head.Mobile.cshtml _Root.Head.Mobile.cshtml should be copied to folder : XXX\Themes\XXX_Mobile\Views\Shared