- All they need is the number of other person, add it and shoot messages, till they block.
- As long as the stalker doesnt send a message, he/she can see your display picture and status message. Depending on how much enthusiastic you are about your profile, you can give out good clues to them, about your name, gender, location and current activity.
- Build user's contact list on mutual existance i.e. only if two people have each other's number saved on phone. So unless you know each other, you cannot see each other online, till both want to be seen.
- By default block people who are not on your contact list. This will prevent random people from seeing you or contacting you or following you
- Allow people to send out invitation request in old fashioned way
- Allow users to choose if they wish to be contacted by people not on their list. If they select not to be, people can't send invitations.