Tagwin - Instagram contests & giveaways made easy
Waitlist API - Quick and easy waitlist with built in referral.
Cominsoon - Build coming soon page to get early feedback
LaunchList - Create waitlist with referral for your product launch
Waitlisty.io - Build excitement for your product by embedding a simple form into your website. Signups will receive a referral code to share with their friends. The more codes they share, the more they climb your waitlist.
VerifyShare - instagram, instagram tools, giveaway, parsing,