Shortwave Bookmarklet - Shortwave is an extensible quick-search and shortcut bookmark.
SendX.io - SendX (https://sendx.io) provides remarketing and retargeting tools for web businesses. You can use popups, landing pages, email, web push notification, automation workflows and FB / Google retargeting to drive more revenue.
Shortwave - Email smarter & faster with a reinvented experience for your Gmail
Brevo - Innovative online Email Marketing solution to manage your contacts, create & send your newsletters and track your results. More than 80 000 clients. Best prices and attractive features.
YubNub - YubNub is a networking web service with a command line–style interface.
ConvertKit - Email marketing software for online creators. We help you earn a living online through an intuitive email marketing automation tool.