So I just got the Mavic Pro a few days ago and the first thing I noticed is that in the DJI Go 4 app you can't set most of your settings unless the drone is powered up.

I assume this is because all the settings are stored in the Mavic and not cached in the app, but it does bring up one issue.

Is there something you can do to lock/disarm Mavic so it won't take off?  Seems like there is the possibility you could trigger a startup or takeoff accidentally while you are setting things up.

Or am I worried about nothing?

Don't worry about it.  Takes a deliberate movement of the joysticks to make it take off that must be held, or physically setting take off in the app which also takes multiple selections.

Take the props off? The auto take-off does require a confirmation step, but just take the props off.

For safety, remove props first, that provides the most safety.  For longer setup times, use a small fan in front to help cooling.  

You have to confirm any take off commands, so unlikely to do it by accident.
But if you are worried, removing the props would be the safest thing to do.

Or am I worried about nothing?

Probably so. I've read about people making many different mistakes and being surprised by a lot of different things, but I can't think of a case where someone took off when they didn't really intend to.

There are a number of folks who didn't think that the motors would spool up while working on their craft(s) when energized.
You can see the evidence very easily if you look for it.
NEVER power up your craft indoors with the props on. Asking for trouble.
Now, if you are intentionally flying indoors, at least you are expecting the props/motors to spool up, and you a somewhat prepared for it.

Certainly take the props off . Many things can happen on electronic devices that can cause the props to spool up unexpectedly .

MavicMule Posted at 2017-5-29 12:27
For safety, remove props first, that provides the most safety.  For longer setup times, use a small fan in front to help cooling.

Good tip with a fan in front. I will use one for the next firmware update, quite hot here the last days..