Top 12 FollowUpThen Alternatives

Boomerang for Gmail is a Firefox / Chrome plugin that lets you take control of when you send and receive email messages.

FollowUp for email is a lightweight productivity suite that keeps your conversations and tasks from slipping through the cracks. Set perfectly timed reminders that arrive at the top of your inbox, right when you need them.

Sales Engagement platform with bunch of sales engagement tools like Email Tracking, Document Tracking, Mail Merge etc. to boost sales teams productivity.

Gmelius is a next-generation CRM and shared inbox for Gmail, tailored to the needs of SMEs that helps you sell more productively, organize and scale your pipeline, manage and build valuable customer relationships.

Sell smarter with email tracking and more

Prospecting, like a boss. Find any email, reach out, measure everything and integrate with your CRM.

Simply powerful CRM. Automates your data to build better relationships and make more sales.

Schedule Emails in Gmail To Be Sent Later

Vocus.io is a productivity tool for Gmail available as a Chrome extension.

Never-Forget.me is a delayed messaging service allowing you to compose email messages now which remain unsent as long as you click a link, at a recurring interval you specify, to continue to postpone the sending of your message

Automatic follow up emails. Keeps on bumping until you get a reply.

Turn your Gmail or Office365 inbox to a Visual Task Board.