Short tap, long tap, double tap on screen... what's the double tap?

[Apollo11capcom]

So if I single tap the explorer screen I get an open padlock icon, tap the open padlock and the lock closes, fixing the current exposure level. If I long tap the screen a vertical gimbal control pops up. When I double tap the screen I get a sorta parentheses looking thing (horizontal parentheses with a smaller vertical parenthesis inside of it) on screen that i haven't been able to figure out yet. Anyone know what it is?

 

[Fly-a-holic]

After a double tap, did you try and pinch the screen? It could be another way to set the zoom. I need to try and dig into the settings to learn more myself.
I recently learned about the exposure level by reading on this site.

 

[Apollo11capcom]

After a double tap, did you try and pinch the screen? It could be another way to set the zoom. I need to try and dig into the settings to learn more myself.
I recently learned about the exposure level by reading on this site.

Same here regarding the exposure level. You don't need to tap the screen for zoom, pinch and unpinch works by itself. If you figure out the double tap feel free to post it here, it's driving me nuts.