Go to your Project Settings > Default Postprocessing Settings. Disable everything but Bloom. If this is all that you are using the HDR for only the Bloom then that is all that needs to be enabled. This should help with increasing the hz.
Everything (including Bloom) is disabled in that section (and was when I was testing the Mobile HDR setting earlier).
Go to your DefaultDeviceProfiles.ini and have a look at this documentation. Effectively this should scale your screen resolution to that of the mobile device.
We’re aware of the r.MobileContentScaleFactor setting - in the past we’ve run with native resolution across all devices (when we realised we weren’t going to get the HDR to run well on low end devices). At the moment we’re running with everything defaulted as we’ve added a fair amount of transparency to the game recently.
As I mentioned above, the Galaxy Nexus appears to think it’s a ‘High’ Android device (when it’s clearly not), so I believe it’s running at native resolution right now. But I have done tests with scaling it right down before (even going as low as MobileContentScaleFactor = 0.2) to the point where the game is unreadable, but the framerate is still unacceptable.