Few days back, screenshots of the Windows 10 Mobile build 10134 were leaked and now we have a leaked video from Chinese site WPXAP.com. The video shows the difference in the build 10134 and build 10127 (apparently both unreleased), with Lumai 720 running the former and Lumia 830 the latter.
Changes pointed out includes the addition of a search bar instead of the search icons present in the app list, the split screen option for the settings menu that is present for the HD devices and more improvement in the Store beta.
The video also questions why the build has not been released for the users? and answers by saying that the build has an update bug which they were able to confirm with their Lumia 1520.
There is no word from Microsoft about any Mobile Build which is not a new story as the company is more concentrated in building the Desktop version of the OS which is due to release later in July.