Send your mail via gmail at schedule time and set mail reminders with Boomerang for Gmail™.

Boomerang for Gmail™ is a Google Chrome extension which manages scheduling of mail timing and also helps in setting mail reminder.

Boomerang for Gmail™ also helps you to keep you inbox clean by sending unwanted mails from you inbox into a folder or label, and then popping up the list at specified time.

The bad thing about this extension is that it is not totally free. You need to pay for unlimited service.

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