VMware Horizon View iAPP VDI + HTML5

The iApp is not setup to support HTML 5 clients. So you need to: create another VS using the same ip as your iApp created 443 vs on your BIG-IP using port 8443, use same pool as your 443 virtual server, modify persistence profile applied to vs 443 to use "Match Across services" option, and verify "Blast External URL" matches "External URL" within your View administration console for both connection and security servers.

Have you successfully connected to a virtual desktop using a html 5 client (without ltm)? If not, verify Horizon View html access has been installed on all your view connection servers, your virtual desktops have both view agent and remote experience agent installed, and verify HTML access is enabled within your pool you are trying to connect.