Could a long press of one of the buttons, say 3 seconds, initiate power down instead?
Yep, there are choices for how to go about this, and it may change. I could imagine a long press working, and it could even "overlay" the other way of doing it.
In fact, in the first iteration, you would hold *both* buttons down at the same time to turn it off. It had the virtue of requiring deliberation (you wouldn't accidentally turn it off). But it was awkward, took both hands, and like your idea of holding just one button, it's "hidden."
Because the second thing you do after dreaming up a feature is to figure out how to explain it to people, and label it. There would probably have had to be a little indication somewhere like "Hold for Power," or some such. And when it's brief like that it gets kind of cryptic. So as I was designing that label I started not liking that approach as much.
In the current iteration, the buttons always do the same thing (move right or left). And 'open' and 'power' are labeled. Maybe not optimally, but they are there. Tweaking will occur.
I believe in a couple of things:
1. Most people don't read instructions (I'm not talking about you and I, BTW, I *love* manuals...)
2. Less is better
3. The more forgiveness, the less frustration
4. Hidden is worse
5. Try explaining to someone how to explain it to someone else
6. Timing shouldn't be too critical
In the current approach, none of the functions depend on how long or short you hold the button. That's pretty forgiving. If a long press turned it off, some people might encounter that as they were trying to set the release altitude. It would surprise most people how wide a range there is in how people press buttons and swipe on UI elements.
P.S. Remember, turning this thing off is something you need to do perhaps once a day, and it's relatively unimportant. More than once I've left it running and let it turn itself off.
