It's nothing sinister Ashley, it's a useful, free site developed by a martial artist (and instructor) who also happens to be a top notch developer and a friend of mine. I see the value in what the site does. It's easy to use, offers a wealth of potential information to students (and instructors) and beyond a few hours of setup requires no more effort than is involved if someone is already taking the time to track attendance, hours, schedule, etc on paper. If people are happy doing things all on paper, that's fine. I just find it contrary to everything that's happened in the world in the last 15 years or so, but ymmv.
Well, we do spend a fair amount of our time in pursuits that could honestly be termed as archaic, so I'm not sure that using the latest technology to aid is is necessary or even desirable. I'm not trying to shoot down what you're doing -- really. But years ago, I had a boss who would patiently listen to us software engineers babble on about the projects that we wanted to do, smiling and nodding, and when he could get a word in edgewise he'd ask, "What is the problem you're trying to solve?" He annoyed the hell out of us at the time, but he was right: you can't go creating solutions unless you know what the problem is.
Automation is a tool. Whether it's the right tool depends on what you're trying to do, just as when you're trying to choose between a hammer or a saw: are you trying to drive a nail, cut a board, or do something completely different? Here in this thread we can see at least three different problems being solved: your app seeks to manage a dojo, other apps would serve as a personal tracker of training hours, still other apps would include additional "workout log" functionality. I can see your app being useful as a back office record-keeper, although I think that in a dojo that already has solutions in place for everything that your app does (or at least, everything that the dojo needs to do), you're going to have an uphill battle getting people to adopt a new way of doing things -- and as someone who's spent a lot of time in the software trenches, it's not really accurate to just put this down to luddism and fear of technology. It's "if it ain't broke, don't fix it" -- or don't spend time replacing it with something that may not work as well.
So, to change over to something new, there has to be an upside, no downside, and not too much pain. Unfortunately, I don't see how you get over the problem of access. How does the information get input? Who has access to it? We can't assume access to the web or to a smartphone, or to any other convenient means of logging your own training hours at the time that you're training. I just don't see any way over that speedbump.