Whatsapp is the most popular feature is group,it helps to connect to friends and relatives.But some times it makes no comfort to your device, It irritating someone add to a group but you not interested., WhatsApp decided to fix the problem by giving privacy settings to deter users from randomly adding others to WhatsApp groups. Recently, WhatsApp rolled out these group privacy settings to everyone.

How to stop in Android devices

1. Open WhatsApp on your Android smartphone and tap the vertical three-dots icon on the top-right.
2. Next, tap Settings > Account > Privacy.
3. Now tap Groups and select one of the three given options — Everyone, My Contacts, or My Contacts Except….
4. If you select Everyone, anyone can add you to groups.
5. Selecting My Contacts only allows your contacts to add you to WhatsApp groups.
6. Third option My Contacts Except lets you allow only selected people to add you to WhatsApp groups.

How to stop in iOS devices

1. Open WhatsApp on your iPhone and on the bottom bar, tap Settings.
2. Next, tap Account > Privacy > Groups.
3. Three given options  Everyone, My Contacts and My Contacts Except.

source:ndtv gadget