Is there any option to lock screen by code like android phone or tablet to nobody unauthorized can use drone ?

That's an interesting question.  I haven't found a way to lock the RC's screen.  There is nothing about that in the user's manual either.  

The other think it's if somebody stole drone with DJI RC he got ease way to unbind drone from account...

Hello there Somer. Good day and thank you for reaching out. I am sorry to say that this function for the DJI RC is not available as of the moment. In addition, I will forward these information to the designated DJI Department for attention. Thank you.

YES PLEASE could we have a Lock Screen (& ability to lock ALL controls)???

I had been waiting for a mini to do active track and got rid of my mini 2 as soon as the 3 came out. I like to use my mini whilst riding but now I’ve discovered setting up the active track can be completely undone whilst squeezing the controller back into my pocket pressing the buttons or tapping the screen then you have to start all over again

Its a nice option and maybe if we are lucky We will have it in a firmware update.