ReferralMagic - Turn your users and customers into referral magnets.
Feather Attribution - A free and tiny javascript library to track UTM tags, ref and referrer data client side so you can store these in your own database.
Viral Loops - Viral Loops is a viral and referral marketing platform to launch ranking competitions, sweepstakes, pre-launch and referral programs.
Voucherify - API-first Promotion Engine for promotions & loyalty.
GrowSurf - Referral software for B2C, FinTech, and SaaS companies.
AWARIO - Track brand mentions & competitors across the web