I have literally had one device of the ledger and another wallet installed on my phone for a very long time. I never stumbled upon your thread or was not around this section a lot to know this one. I will surely use this software to turn my old device into a hardware wallet. My method of doing it air-gapped is very simple, you turn it off and don't turn it on until you want the funds out of it. Lolz. Very poor method to work with it but so far it's far better than my ledger. I lost the ledger once and also found it but obviously one could not forget the big old mobile device laying around which just lost.

I will graciously download the AirGap Knox on my device which I have dedicated for the same purpose mentioned. I will try to turn it into a hardware wallet with your guide and hopefully will write down a review here or in the new thread itself. Thanks for this.