You cannot let someone else control your screen. This is fine by me, I never want someone controlling my screen anyway. If I want to collaborate with them, I use any number of better ways to get them shared access.
You cannot control other folks screen. This is often a challenge as too many people offer this up as the only way to remotely help them. I hate doing this because even in Windows the experience is utter garbage, but sometimes the other party just forces my hand.
Using it from chrome is how I use it.
Two limitations: