Is there a simple email-based spaced repetition tool?

How would you expect to interact with such a system? Part of the way Spaced Repetition works is to adapt its timings based on whether you got things right or wrong. Times to recall prompts can be less than a day, down to minutes, are you expecting to get an email every minute until you respond?

I don't see how the system can implement the fundamental underlying algorithm and still work via email. I've written Spaced Repetition systems, one that works on the command line, another that works via a web page, and I'd be interested o now how you envisage something like this working via email.

Yes, it's an open source software called Dnote [0]. I wrote it two years ago and have been using it since.

The two main features are:

* putting in new information without switching environment

* getting automated weekly email digests

Like you, I wanted to avoid building habit around a separate app because that would require me to switch environment every time I want to write something, thus losing context of my current task. So I made Dnote work as a CLI, browser extension, IDE plug-in.

While I'm not sure exactly why you want an email spaced repetition, for me, the reason was that I never looked back at my past notes. The solution to this negligence was to automate the spaced repetition via weekly email.

I suspect we are trying to solve a similar problem. Hope my software can help.

[0] - https://github.com/dnote/dnote

I was wondering about your rationale for not using another app like Anki. I'm a big fan of email and loved the integration of reminders with email of the like provided by Inbox (and sadly missing from Gmail as of today).

But I am also cognizant that there's a context associated with different apps. I've been using AnkiDroid for over a decade now and the context the app provides (mental context that I'm learning something) helps me focus better. Email is usually a stressful context in my mind which reminds me of deadlines and tasks to complete; so I like to keep both of these contexts separate.

I built a website that (simplifying here) quizzed users once per day, it wouldn't be too hard to change this into a spaced repetition tool.

Would you (or anyone) pay for it? How much? It is interesting enough that I'd be willing to work on it.

You can send scheduled emails via Google Sheets (Tools -> Macros -> Triggers).

I did so for a "Your random word for today." kind of setup.

It's not quite spaced repetition because the amount of time in-between repetitions doesn't vary but it's close enough.