How are you able to send whatsapps to people you don't have a prior conversation with ?
I am doing the same boat...and was working fine until i lost & replaced my old phone. All conversations were lost, and this makes it challenging to use whatsapp for any non-group conversations (since I can't start any).
Others can still allow access to their phone book and the information stored in them about you will be transmitted and saved at Facebook, won't it? Is there a way to disable that?
Exactly this. I recently started a twitter for my academic career. Didn't share my contacts or anything (I only follow academic twitter too). I get tons of suggestions of people I know and several have followed me. The information is from their contact list because twitter knows my number and connected us. There's a clear benefit to this, but there's also privacy concerns too. The lack of control over this is what is concerning.
As I've seen on WhatsApp on every smartphone I've had: when you download WhatsApp and tap the "New chat" icon in the upper right corner, the app SHOWS YOU a list of everyone from your phone's contact list who has a WhatsApp account. They also show the list when you click "Chat" at the bottom and then "New Group."
