Snailbox - Schedule your email at specific times and recover the time you're losing to your inbox.
Minutemailer - Email Marketing. Simplified.
Inbox When Ready - Protect your focus... hide your Gmail inbox by default
MailerLite - Affordable Email Marketing Software. Get all features (Segmentation, Automation, A/B testing) for up to 1,000 subscribers & send unlimited emails for free!
Clean Email - Clean Email is an online service that empowers you to take control of your mailbox.
PixelBlock - Block email open tracking inside of Gmail