NudgeMail

This is highly underrated, an absolute gem! I use it to schedule my spaced repetitions. It's a lifesaver. I hate gmail but using this one with gmail is super convenient. Just sign up for a new gmail account & create new contacts. I send my emails (whatever I have studied that day, from whichever resource) to all my contacts, which are- 24h@nudgemail.com, 2d@nudgemail.com, 3d@nudgemail.com, 7d@nudgemail.com, 14d@nudgemail.com, 21d@nudgemail.com, 41d@nudgemail.com, 61d@nudgemail.com, 81d@nudgemail.com, 101d@nudgemail.com, 5mo@nudgemail.com, 6mo@nudgemail.com & I never have to worry about taking care of my revision needs, this reminds me whenever it's time. Use gmail because it allows you to mass mail all your contacts at once. Click on 'to' & select all your contacts from there with one click. That's it! This is completely free service! You may pay if you find this helpful, but you don't have to. Also it seems that their payment link is dysfunctional, and seems like they don't care.