Anki's webbased app leaves a lot to be desired. There's a lot of barriers when it comes to sharing / editing community made cards. You have to physically upload your deck, and people have to have anki installed on their desktop normally to preview said cards.

You can view ankis webapp here https://ankiweb.net/. There's almost nothing on the homepage. Just a login. Not exactly enticing for users looking to review their cards online. Anki's web interface is extremely barebones. Its more or less the equivalent of a dropbox folder or an amazons3 storage box. Not a place to share, debate about the writing / content on cards, a forum where people suggest new features on ankiweb, etc. Its also not the place you preview your cards either. Ankis webapp doesn't let you upload images through there. Everyone puts images on their cards via desktop app

Ankidroid, a 3rd party app, makes anki extremely useful. I currently make all my cards on desktop, and then preview all my cards in the morning going to work everyday.

Anki is also extremely client-side customizable, which is one of its biggest pluses. I currently use about 5 or so plugins to make data entry more streamlined. I have some other plugins that read/writes to the database that affects both ankidroid and ankidesktop app.

Comparing this to "soyoulearn" or "memrise" or "duolingo" the site is much more inviting for community driven features on its webapp.

However, the problem with a webapp with a centralized database is two fold.

First, it degrades the quality of the cards and card deck. Imagine you had to study for test in college. You could write your own cards, or borrow your friends card who took this test last year. The content of the test might be exactly the same, so the cards are still relevant. However, since you didn't create the cards yourself, you might not necessarily understand the context of why it was made. What specific situations that card is useful, and the hard earned experience to make it. You don't have the same appreciation of a card created by someone else than if you made it yourself. You don't get the "aha!" moment when reviewing someone else's created card, e.g. "Oh I made this card in the university Library and my friend so and so said this great idea that I jotted down on the card".

Second, it encourages laziness during card creation. Why create a deck when someone else has made one? Especially if its community driven and approved.

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TL-DR

In summary - a community driven flashcard webapp (soyoulearn.com) is only better than a customizable client-side app (anki) for the following reasons:

- If you don't want to make cards, and don't mind shallow content behind each card to save yourself time

- If the cards you are making are predictable in nature and well established( e.g. cards for a specific course, languages, etc)

- If you don't mind purely memorizing a set of cards without having a physical memorable moment attached to that card, and understand that these cards have less value than ones created by yourself.

A client-side app like anki will always be better for the following reason

- If your card was hard-earned, e.g. your a programmer and made a error, you want to remember how you solved it

- You read a niche science paper that only a handful of people look at, and draw meaningful insights from it

- If your card's content is extremely niche, meaning there's going to be few people making cards related to that content

- If your card might possible be outdated overtime (e.g. the changing state of javascript / webdevelopment - your card regarding a specific library might be irrelevant next year), and you need the ability to fine tune your deck easily (suspend card).

- Your cards are created at random, they aren't created based off of a syllabus or university course

- You want to have the highest quality deck possible and scale it upwards

I think both have their pros and cons. For me, I would definitely prefer to dump all my language learning on a webapp / use premade decks, but all my programming / hard earned experiences on anki. As of now I seperate my cards based on the context of how they were created - were they created in a bulk, batch process (e.g. memorize a set of APIs), or did I have an actual question, and I created that card as a result?

Otherwise I mix all my cards in one deck