Hey, George. Welcome.
It seems that your sites are down this morning. I'm trying to hit them from mobile data in the Carolinas.
Also, if you take a look around here I think you will find that we are not really in your target market. There are luddites and vagabonds, old school sailors and boatyard bums; and even some geeks too. Of the varied approaches taken by members, all are worn as a badge of courage and solidarity.
I would never use a cloud based app as one of my goals is to be disconnected. I saw your Utube that suggested it could be used offline, but I just wouldn't. That's not to say I won't keep an inventory on a tablet or a RPi, but I'd be better served by something I've built myself.
Good luck.