Show HN: I combined spaced repetition with emails so you can remember anything

[iskrataa]

Hey HN,

I am a student shipping apps in my free time. This is my 4th for the year!

Non-fic books and podcasts have been part of my life for years now but I always struggled with remembering what I’ve read or listened to. I wanted it to stick even after years.

My notes list grew large but I never really revisited them. That’s why I created GinkgoNotes.

You can enter notes you want to recall and leave it to the app to create a personalised (based on spaced repetition) email schedule. That means you’ll get your notes emailed to you a couple of times exactly when you should read them again (based on Ebbinghaus's Forgetting Curve) so it’s certain that you’ll remember them.

I hope this will be helpful as it was for me. Would love some feedback!

Iskren

[gravity2060]

This is so cool and something I’ve wanted for a long time, but it isn’t quite right yet (for what I personally want in an app like this.)

I am your target market, and I’d buy the lifetime /annual sub in a second if it had these features:

I want control of the SR sequence or, I want to know what SR algo you are using and know it is best practice model. The landing page says 4 sends, but that isn’t true SR.

The next thing, I’d want to see all of my “cards” or information pieces when I am logged in, so I can see and edit and delete and keep the database clean with a total view of content. The next thing I’d need (maybe you have this?) is for the email to effectively be a flash card, where the email content is the front and a link the email takes me to the “back” of the card so I can’t use cloze delete and other techniques. The last thing is bulk upload of content via a csv so I can bulk import mochi /anki / llm generated content.

I wish you luck with this and would (selfishly) encourage you to not ship so many different things, and instead encourage you to pick one and make it best in class for niche users like me who would spend and spend on premium solutions, but won’t spend on superficial implementations.

[iskrataa]

Can't thank you enough for the feedback. These are all great ideas which I'll look into.

I was wondering what is your experience with Anki? Are there reasons you are looking into alternatives or do you just like the idea of getting stuff by email? Thanks again!

[safety1st]

On the topic of SR specifically, what does it mean to be best in class? I am just a layperson who uses a SR tool or two and has a passing interest in the topic, but the Wikipedia article on SR gives the impression that there are a variety of algorithms out there and none are established by research to be definitively better than the others, in fact the Criticism section mentions a study which found that absolute spacing was just as good. https://en.wikipedia.org/wiki/Spaced_repetition#Research_and...

The OP said he's using Ebbinghaus' "forgetting curve" which is not exactly a SR algorithm but something similar, there is an actual formula associated with it - https://en.wikipedia.org/wiki/Forgetting_curve

[wellthisisgreat]

Hey not to distract from OPs post, but I wanted to get into SR for a while, and your "what is your algo" question aligns with my line of thinking when approaching new methodology.

Could you please share your SR tech stack? Are there good apps etc., that can make the process a bit easier? The pen-and-paper approach I used in uni for learning kanji / new languages has scarred me somewhat, so I am eager to try something tech-heavy.

[simple10]

Congrats on the launch! I second the request for lifetime pricing option.

Also, the jump between $4/mo to $59/mo could use more explanation to justify the price gap.

It's worth considering listing GinkoNotes on AppSumo if you decide to offer a lifetime deal. I think it would do extremely well.

[crashabr]

You should try Readwise

[latentsea]

Why email at this point and not just Anki?

[rahimnathwani]

This is an interesting approach. Congrats on shipping!

I worry that it won't be effective. Systems like Supermemo and Anki work because of:

1) Spaced repetition (showing you the thing at the right time).

2) Retrieval practice (having your brain practice retrieving the thing you're about to forget).

3) Feedback and automation (using your self-rating to schedule the next review).

You are doing #1 and #3.

But you totally skip #2, because you show all the info in the email. So, unlike Anki, Supermemo or Quantum Country (which someone mentioned in another comment), there's no front/back or cloze deletion, and no retrieval practice happening.

Perhaps putting the question in the email subject and the answer in the email body would work?

[iskrataa]

Thanks for the feedback!

I agree, and this is something I thought about a lot during the design process. In my experience, just looking at the note (#1 in your example) helps a lot more than no repetitions (which is obvious of course), but it's still a huge improvement compared to my previous flow.

As for repetition, I was thinking of replying to the email with what you think is the answer and letting an LLM decide if you remember correctly. Is that something that sounds effective to you?

[david_allison]

More information on #2 (colloquially known as 'active recall'): https://en.wikipedia.org/wiki/Testing_effect

[wrboyce]

Very interesting concept! I was about to dive right in when a voice in my head reminded me that my inbox discipline is terrible and I don’t need even more automated emails that will serve only to increase my unread count (which currently stands at 16878 in my Personal inbox).

Have you considered expanding this to notify via other mediums such as iMessage (if possible, this would be my preference) or the presumably easier WhatsApp/Telegram (the Telegram Bot API is pretty great, I’d imagine would be very easy)?

I’d also echo the free trial sentiment expressed elsewhere in the comments, take the mythical drug dealer approach and get ‘em hooked on freebies!

[iskrataa]

Yes, that's definitely a major drawback for people who are not so active via email (or got their inboxes spammed by marketing haha).

Will explore some options with the messaging apps, thank you! Do you think at this point it's not easier to open a specific app for that or there's a reason you prefer it to be via a messaging app?

[TripleChecker]

Neat idea! I might consider pushing a free trial more since this feels like the type of product someone could begin to rely on and then be more likely to upgrade. A few positive testimonials wouldn't hurt.

A couple minor link fixes on your homepage, see here: https://triplechecker.com/s/230357/ginkgonotes.com.

1) Blog on footer is broken link 2) Affiliates on footer doesn't take you anywhere

[iskrataa]

Yes, I agree with both statements. Although I'm just starting and don't have any testimonials yet, I was thinking of sending an email to users requesting testimonials in exchange for the premium plan.

Just fixed the footer, nice catch! Shipping fast comes with some faulty copy pastes I guess...

[namaria]

Storing facts is a poor proxy for acquired knowledge or skill. When you are good at something, you know a lot of facts. Trying to memorize facts to get good at something is inverting the order of factors. You memorize a lot of facts about a domain because you spent a lot of time and attention in it. But finding shortcuts to memorize facts won't in fact give you the actual knowledge and skills, just a way to mimic them convincingly.

[gimmecoffee]

I recently started learning Japanese and "storing facts" using spaced repetition, and it's great for learning Hiragana / Katakana.

It's also very useful for things like passphrases.

Sometimes, you just need to memorize things.

[siva7]

This is a common fallacy around science students who use anki for the first time. Smashing a deck without accompanying learning ressources won't lead to connecting the dots like you would in a traditional learning setting. So given an exam you would probably fail as you can't connect the dots because you just memorized facts in a random order. The exception is of course language learning for which anki and spaced repetition was made originally because random order doesn't matter and connecting facts neither.

[nefrix]

This is such a smart answer. i am adding this comment so i can remember where to look when I am thinking of re-reading your comment about memory;

For me, more than memorising things, is creating paths in order to find that piece of information when need it; and yes, you are right, we memorise when we need that information to apply it in a specific moment;

[geros]

I developed an open source app that tries to solve this problem. Active recall at the topic level with spaced repetition email reminders using FSRS algorithm. https://github.com/Gerosullivan/Learntime

[tsekiguchi]

Readwise also has this feature. I get a daily email with a random assortment of highlights that have been pulled in from multiple sources (Reader, Notion, Kindle, etc.)

The product benefit in their case is that it's kind of like Zapier, but for notes.

https://readwise.io/

[RamblingCTO]

Gingko notes have been a thing maybe 10 years ago? I'm not sure if I remember correctly, but wasn't graph-based note taking? Was really cool!

The idea of spaced repetition via email reminds me of readwise as well.

[shanusmagnus]

You're thinking of this [1]. Super duper cool idea, ahead of its time. Author seems to have transitioned to a ludicrous pricing model, but I suspect it's because the people who like it really _love_ it. I used to be among them, but then switched to org-mode .

[1] https://gingkowriter.com/

[iskrataa]

Yes, Readwise was sort of an inspiration for me too, but looked like wasted potential as they don't track or use any algorithms for you to remember, and lack support for external links/sources (I may be wrong here).

[dirkc]

Well done shipping your project! I like the low-friction demo on the page! I assume I'll receive an email in a few days from now? Are you using those emails for marketing/a mailing list?

[iskrataa]

Thank you! You're both right—you'll get your repetitions, and I'll add you to the user mailing list (unless you opt-out).

[alwayslikethis]

With the number of cards I have in Anki, something like this is going to fill up my inbox. Recent Anki versions ship a much more advanced algorithm called FSRS which performs much better (fewer reviews for the same recall). If you haven't tried it in some time, I recommend taking another look. Also, many note taking programs have ways to export to anki, which is probably more pleasant than adding notes directly.

[BenMorris-Rains]

Cool idea, can it just be an app that sends me notifications instead of the email? Anything that goes to my email is basically a black box and I won't see it. I am an email hoarder and I don't clean them up... Once every other year or so I'll try.

The only thing that helped was routing "updates" and "promotions" straight to my trash, but I miss things sometimes that way.

[Scea91]

Seems like the root cause is not email.

I am curious how “another app” would be better in your situation than just setting up an email rule (3 min task at most) for this mailer if you truly care about it.

[complianceowl]

What the --

This is such a great idea! I've had this same problem for as long as I can remember, and I feel like most intellectually-oriented folks have this same problem, as well.

My work firewall blocked the site, but I will check this out later :)

[iskrataa]

Thank you! Glad you like the concept. Don't hesitate to shoot me an email if you have any suggestions/features you'd like to see :)

[bturtel]

This is very cool. Reminds me of Quantum Country (https://news.ycombinator.com/item?id=30467585) but for everything else in life.

[ianbutler]

Email is the only thing I have conditioned myself to reliably check so this system probably has the best shot for me. Nice job, will try it out. Ive been meaning to make a real attempt at learning Japanese.

[iskrataa]

Thank you! Have fun learning Japanese!

[betimsl]

I use mochi.cards and am very happy. It has a really good app and it's very privacy friendly. I recommend it to anyone who is studying or preparing for any event that requires efficient memorizing.

[xkbarkar]

I have 3 email in-boxes. One ancient rarely used since the early 2000, my personal daily email and my work email. Between then there are some 100k unread emails.

I am not the target audience for this service.

[vundercind]

I sometimes go most of a week without checking any email address. I’ve gone a month without looking at my personal one. It’s basically just for transactional mail, I don’t get things from people there.

[exe34]

I do an annual amnesty, every email goes into archive on the first of January.

[iskrataa]

I think there are a lot of people like you, so I would definitely look into other ways of communicating. Thanks for the feedback!

If it was over WhatsApp, for example, would you be interested?

[christin369]

This is really impressive! Would you mind sharing some analytics like subscriber count or DAU? I'm curious to learn more about how your platform is performing. Thanks!"

[iskrataa]

Thank you! Sadly, it's just at the start of the project so I don't have anything to share yet.

I'll give an update after some time of collecting metrics. You can also follow me on X to be in touch with the project.

[moojacob]

I really like how you can create a note from the landing page. 1) it helped me understand how the app worked better than any screenshots or videos while 2) nudging me to sign up.

[jdthedisciple]

I made the exact same thing except with notifications instead of email.

I called my app "Mnemonist".

My last as just hasn't gotten around to shipping it yet...

[pugworthy]

It seems you've made a digital mnemometer!

[kazinator]

I can't find them who would use this over Anki or AnkiDroid.

I have hundreds of items to review. I wouldn't want that in my inbox.

[iskrataa]

I get you. In cases where you have that many cards, that's definitely not for you.

My case is rather 2-3 quotes from a book I just read of 5ish articles per week which I find interesting and don't want to forget (so it will email them again to me after some time so I can reread). Thanks for the feedback!

[Cotterzz]

Interesting. I couldn't see myself using a tool like this for bulk remembering of things. And I don't think it would be practical for that. But for specifically important things like certain words my brain like to forget from time to time, numbers I need to remember or a very important hospital appointment, this could be very useful.

[MaxPock]

I wish there's a away I could upload my screenshots then they get e-mailed at intervals

[iskrataa]

For now, I have found a workaround which is to just paste the screenshot URL if you are using one of those apps that automatically uploads them.

I'll let you know as soon as the image upload is live!

[guluarte]

I'm a big fan of SuperMemo16, if you could add incremental reading that would be great.

[wowsoleet]

The idea is good but:

1) Paid model, $10 for an email on timer? Copilot, Spotify and Windsurf charge the same. Won't pay on principle THIS amount of money for a service which is done self-hosted in 30 minutes with ChatGPT, neither will a normie buy paid calendar, no offense. $1 is realistic, still you're gonna be profitable and much more scalable imo. Trial period of 2 weeks is mandatory

2) I almost never read mails, plus email notifications are inconsistent if you're not inside an ecosystem, e.g. Apple/Google. For me it is not a reliable way of communication

[joshdavham]

This is a super cool idea!

Also, which spaced repetition scheduler are you using for this? FSRS?

[iskrataa]

Yes, it's FSRS based on this article

https://github.com/open-spaced-repetition/fsrs4anki/wiki/Spa...

Huge thanks to the dude.

[OxfordOutlander]

Looks awesome - would you mind expanding on the tech stack you used?

[andai]

The comments here remind me of the HN comments when Dropbox launched!

[andai]

Cool idea! What were your other 3 projects this year?

[dirkc]

This looks like it might have been one of them? https://ginkgovest.com/.

*edit* seems different - google search led me astray. I didn't realize ginkgo is a tree with a distinctive leave

[iskrataa]

I kicked off the year with a web app that summarises foreign books using AI.

2nd is a desktop emulator of an iPod (macOS only)

3rd is a Stardew Valley tool

Let me know if you need a URL for any of them :D

[recursive]

> you can remember anything

Except to check your emails.

[slwvx]

Could be a good feature for AnkiWeb.net

[iknownthing]

Wish this existed when I was in school

[aboardRat4]

Where is the code?