RafflePress - RafflePress is the best WordPress contest and giveaway plugin. Grow your email list, followers, and website traffic with viral giveaways in WordPress.
Thunderbird - Thunderbird is a free email application that's easy to set up and customize - and it's loaded with great features!
UpViral - Referral marketing platform enables anyone in running effective and profitable viral marketing campaigns – in minutes.
Mailbird - Mailbird is the best email client for Windows 7, 8 and 10
Tremendous - Tremendous is a customer and employee loyalty platform that allows companies to reward their customers for surveys promotions and referrals.
Microsoft Outlook - Organize your world. Outlook’s email and calendar tools help you communicate, stay on top of what matters, and get things done.