I use Jalup Main, am currently about 3500 sentence cards in. The plan is to finish 1500 more and then create my own sentence cards from the books I’m reading. (To put that into context, I am currently fairly comfortable with easier native podcasts and novels. Probably solid N3 working towards N2?)
Jalup basically has two things: Kanji Kingdom, which tries to teach you 2300 Kanji meanings through mnemonic chains and Jalup Main, which is 5000 sentence cards. Of those 5000 sentence cards, 1000 are in English > Japanese, the 4000 sentence cards afterwards are in Japanese > Japanese, meaning grammar and vocab is taught with Japanese definitions. All the sentence cards are +1, meaning there is only ever one unknown piece on the card. (The total amount of sentence cards is actually 7k, but from what I gather most people move into the wild after 5k)
Jalup Beginner (The first 1000 of 5000 cards) teaches you most N5+N4 (and some N3) grammar through fairly minimal explanations and seeing said grammar used over and over again in the sentence cards. (There’s also some vocab, but not a whole lot)
Personally, I loved Jalup Beginner. If you’re not a textbook kind of person it’s a really nice way to learn grammar in a consistent way (e.g. do 10 cards/day). The grammar within is a fairly good primer for easier native material, so you can now move on to read things like よつばと!
Jalup Intermediate (Cards 1001-2000 of 5000) gets you started on J>J learning. To be honest, “Why you should start learning Japanese in Japanese!” is a whole topic on its own. My opinion: Everyone should be doing J>J, but when you start doing it depends. Doing it on your own at N4 seems crazy, not doing at N1 seems like wasted potential. Jalup throws you into the pit around N4, which is only possible because of the premade decks. The first 100 cards are brutal, the first 300 are rough, after the first 500 cards you’ll be glad you stuck to it. Without a doubt, the weeks in which I was tackling J>J was when I saw the largest gains within my Japanese abilities. (There’s also some grammar in JI, but the focus shifts towards vocab)
Jalup Advanced, Expert and Hero (Cards 2001 to 5000) is more vocab and grammar in J>J. Nothing much new to it. You could move on to create your own J>J sentece cards after Intermediate, but it would still be somewhat of a drag because of your limited vocab size. With each deck your transition into creating your own J>J sentence cards from native material gets easier and your purse gets lighter ![:stuck_out_tongue_winking_eye: :stuck_out_tongue_winking_eye:](https://emoji.discourse-cdn.com/apple/stuck_out_tongue_winking_eye.png?v=12)
So much for a “short” explanation on Jalup Main.
Would I buy it again? Yes. Learning grammar and vocab through sentence cards ended up being my preferred method of study. I’ve also grown to love J>J and wouldn’t want to go back to E>J, but that’s just me. I do however recognize that I am lucky enough not to hurt for the money I spent on Jalup.
The first 100 cards of every level (Beginner, Intermediate, Kanji Kingdom, …) are available for free in case you want to try any of it. However, the first 100 cards of Jalup Beginner are really basic.
I’ll also tag @trombonekun91 who uses Jalup Main and Kanji Kingdom and @sycamore who uses Jalup Main but isn’t as religious about J>J as we are in hopes of them giving you their view on it.