MPH, please about hud HOT 5 OPEN

Looks promising.

from hud.

Probably not. The big advantage of the current state is that there is absolutely nothing to configure. There are about 4 countries which use some variation of natural units (those are Liberia, Myanmar, UK and US, and some islands, most of them dependent territories), and big majority of the world drives in km/h.
https://en.wikipedia.org/wiki/Miles_per_hour

I'm sorry, but that's the compromise I'd like to take. I consider the "no config" rule a guiding principle, which has major safety implication, since it discourages fiddling with the phone while driving. The phone is often at the border of arm's reach, and trying to change something is dangerous.

Saying that, I admit that the unit system is something that user would probably select once in lifetime. It may be possible to derive the unit from some system setting. I'm not aware of such setting in Android. I rule out the language, since people may have set different language than their country's (or country they currently are traveling to). I for one have set en_GB, because I like my devices to be in English to be able to google settings and errors.

from hud.

I can see that being correct in 201 of 205 countries would suggest that no setting is needed, but UK & USA between them are probably a very significant proportion of the Android market.
Can I request a screen as the app starts with this setting on? This screen to timeout in maybe 10 seconds if there's no interaction?

from hud.

I have no idea how large or awkward it is to access, but Android has a passive location service from which it should be possible to derive the current country.

from hud.

https://github.com/westnordost/countryboundaries is an android library to find offline the country from coords.

from hud.