Waitlist API - Quick and easy waitlist with built in referral.
NeverBounce - Real-time email verification and cleaning to ensure emails never bounce.
LaunchList - Create waitlist with referral for your product launch
ZeroBounce - Removes invalid emails from your list to prevent email bounces from ruining your deliverability.
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.
Email List Verify - The Fastest Way to Improve Email List Deliverability and ROI