I have a flashdrive (thumb drive) that I use to play MP3 files with
music or podcasts, in the car, either by plugging straight into the car
radio, or with a $15 gizmo that plugs into the cigarette lighter and
broadasts in FM to the radio.

1) If I turn off the radio or gizmo or unplug the flashdrive, it starts
up again either (where I left off or iirc much more likely) at the start
of the song or segment I was playing when I stopped the previous time.

Where is this information stored, in the radio or the gizmo (whichever
the flashdrive is plugged into)? Or in the flashdrive itself?

How is it stored? If in the flashdrive, in an identifiable file?

I could learn part of this by testing, but I'm running out of time, and
I'm sure you'll have a little more to say about the topic anyhow. If
it's stored in the flashdrive, I can have it keep position in more than
one flashdrive, putting music on one, science podcasts on another, and
history podcasts on the third.

2) There are one or two vacant FM radio frequencies, present on the
radio but not used, at least in the USA. Either was a good choice for
my gizmo (since my own car radio isn't new enough to play directly) but
it seemed that the very low frequncy, 87.7 or 9, led to a great lack of
fidelity in the sound. Was this my imagination, since 88.1 works just
fine. It seems like 2 or 4 tenths of a megahertz wouldn't make much
difference. (At the high end, I think 107.9 is often in use and I
don't think radios go higher than that. And googling told me that the
only unused ones are at the bottom.)

3) While I'm asking, my 2005 Toyota radio has a GPS on the screen, but
EVERY time I turn it on, I have to touch something to agree to the legal
disclaimer that show. Every time. And I don't really need GPS anyhow.

Are there newer after-market radios that either a) show GPS but don't
expect me to do this every time, or b) use the screen for something else
altogether, not counting controlling the radio or a rear-view camera or
watching movies**???. I can't imagine what else there is, but I've
known for a while that I don't have much imagination.

**I'll neve watch a movie in the car (certainly not while I'm driving),
the rear-view camera is on only when I'm in reverse, and I'm sure there
will be a way to control the radio. I'd rather have mechanical buttons
but it's 2-din and I'd even more want to have some new-fangled gizmo.

Thanks a lot.