Especial case of app rejection by guideline 4.2

Hi all,
There are plenty of posts about app rejection related to this 4.2 guideline (usefulness of your app is limited by the minimal amount of content or features it includes), and mine is not an exception.

Every case you can find in the web is different and some cases are indeed very clear (web apps just ported to iOS, simple apps just launching other apps, etc), but some to time you find incredible cases where it seems the reviewer is not really willing to understand your app. I feel I am in this case, and I just hope to find here a good samaritan that can give me a tip to refloat my app :(

In the "Next Steps" of the resolution for this type of rejection they say "We encourage you to...offer compelling capabilities or enable people to do something they couldn't do before or in a way they couldn't do it before...".
And this is why I said I am on a special rejection case, because my app clearly does something that currently cannot be done anywhere else (not on a web app/service, not in any other mobile app, even on Android).

The scope of my app is limited to a community (paragliding and base jumping sport community), so I can understand it is not of course "useful" for everyone, but that is the very same than the usefulness of Candy Crash for my grandmother isn't it?

Rejection after rejection I have been improving the UI (so right now the user is basically UI driven), I have added persisting data to the app, etc etc, but they keep saying that my app is useless or not unique, when in fact it is very useful (for its target community) and very unique as nobody else is doing this (basically my app is performing flight model calculations based on Maps and an external elevation model so you can visualise in a theoretically way where and at which altitude you would be flying your paraglide or your wingsuit when launching from a certain point in the map).

I tried to explain my case to the reviewer, in case he/she does not understand the real purpose of my app (for example, if you try to use my app in the sea you won't get any data of course because you are at 0m elevation, so no possibility to fly in there) but I am only getting "auto replies" saying my app is still not compliant. I also tried twice to have a phone call with them (as suggested in an email I received from Apple) but they never contacted me...

I put a lot of hours on this app (a free app BTW), and I basically feel I am being rejected without any valid reason, and the worst, I don't know how I can counter back all these arguments if they are not listening to me.

Sorry for the frustration in my post. I really hope somebody can give me a hint here. Thanks
Especial case of app rejection by guideline 4.2
 
 
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