Click on the pink Invite button at the right bottom corner of the app.
There are five available options on the application
a) Share Symbol: after clicking on this option you should be able to share the referral link using Email, Facebook, Twitter, SMS, and many other available options on your phone.
b) Social Options Symbols: Here you have the option to directly share the link via your preferred social network - be it Facebook, Twitter or Whatsapp.
c) Share via SMS: Here you will be able to send the invite code via SMS to your friends via giving access to your contact list to Mode.