Thanks to the extra information.
Stas Yatsenko wrote:
I'm not surprised LG failed the mouse test, I'm fairly sure this phone doesn't have USB host at all. However, Samsung S4 does, it should have at the very least detected a mouse. Which leads me to a conclusion that the adapter you've tried is actually not OTG.
In meanwhile I found extra information, did tests, contacted LG support, that state my LG don't have USB host at all. As for the test with my daughters phone, it was not with a Samsung S4, but with a Samsung "Fame". A typical young girls phone, one of the cheapest models. Maybe it do have some hardware USB host possibilities, but is lacking USB-drivers ???
As for the USB OTG cable, it is from the brand
< DeLock >
A brand of reputable state, so I guess the cable is not faulty.
But have no other possibilities for testing now. (My daughter with Samsung Fame is not with me now).
As for USB host possibilities I tried some apps that has several testing procedures.
The most useful I found is
< USB Host Diagnostics >
It do some test to hardware possibilities, OS, ports, drivers etc. Afterwards you can send the report to a general website database where people can look if devices are supported. Very handy. See
< HERE >
Screen-image of a device that do support USB host options:

Resource of the image
< HERE >
This website has useful information in general as for USB OTG compatibility issues.
I also found extra USB-drivers that can be of help if the mobile device do have hardware capabilities
for USB hosting, but lacks drivers for it.
See freeware version
< HERE >
See Donate version
< HERE >
Specific website of those drivers with more useful information
< HERE >
As a special note for users, do read the warnings as for power draining hooking up devices to the USB-port with the extended drivers, normally not used or connected. A separate powered USB-hub can be helpful (as I did in my first test already as written in my first message).
It would have been nice if my LG phone worked all through USB, but it is not my intention to exchange my phone for another type. (I purchased the phone separately). The devices that will work are usually more large and heavy as my LG phone. The handling as for a "mobile phone" then comes into question for me. That is the main application for me in using such a device. For shooting a camera tethered I can still use my laptop, only more clumsier.
By all those testing, I experienced a quite high draining of power of the battery of my mobile device. So the usefulness of using a mobile for tethered shooting do have their limits anyway.
Stas Yatsenko wrote:
P. S. It's true that Remote can work over wi-fi and USB support is no longer strictly required, but we haven't lifted that restriction yet.
I could download DslrDashboard without restriction.
But of-course I met the same problems as for USB host compatibility as with Helicon remote.
Tested USB host compatible Android devices for tethered shooting, for another camera app
< HERE >
I guess it can be a good guide which Android devices are compatible for use of Helicon Remote to.