With a referral contest, your social media communities will grow because, in order to participate, competitors must sign up and share their participation, encouraging their friends to do the same. The participants themselves will be in charge of promoting your campaign and making it go viral, therefore raising awareness of your brand.
You’ll also grow your database easily. To validate participation, participants must sign up via an entry form, that you can customize with the fields you need. This can be valuable information you can use for future marketing actions.