Netflix has said that it will support HDR on mobile devices, although at the moment this only applies to content viewed on the LG G6, which supports Dolby Vision. It is expected to be available on the Samsung Galaxy S8 shortly (it seems that a bug means that S8s are showing an icon for HDR, but the content is not shown in HDR). The LG needs to be running the latest software.
Analyst Comment
We were impressed with what LG was able to achieve on the G6 when we saw it at MWC (Dolby Demonstrates Dolby Vision Smartphone Performance)