A puzzle book by e-mail, once a month
On the first of every month you get one new book of 100 logic puzzles as a PDF made for an e-ink tablet, and every puzzle in it has exactly one solution.
Issue 1 is dated October 2026: 100 puzzles from ten kinds, ten of each, in three page sizes (157 x 210 mm for e-ink, A4 and US Letter). The contents page links to every puzzle, every puzzle links to its solution and every solution links back.
Test modeBoth buttons lead to Stripe test mode. Use the card 4242 4242 4242 4242, any future date and any CVC. No money is taken and no issue is sent.
3.90 €a monthVAT included, nothing added at checkout. One new issue on the first of every month, cancel whenever you like.
Download the free sample Buy Issue 1 on Etsy, 4.90 €
Seller: ARLing s. r. o., Company ID 56583486, Bratislava, Slovakia. The payment is handled by Stripe as merchant of record (Stripe Payments Europe, Ltd., Dublin): you buy from Stripe, which collects the payment, issues the receipt and pays the VAT, and ARLing supplies the files. By paying you agree to immediate delivery of digital content and accept that this ends your right to withdraw from the contract. Terms · Withdrawal
How it works
There is no account to make and no app to install. The whole product is a PDF and an e-mail with the link to it.
Card or the payment methods Stripe offers in your country. The subscription renews every month, or every year if you took the yearly one.
Within a few minutes an e-mail arrives with the download links for the current issue, in all three page sizes. Every following issue arrives the same way on the first of the month.
Send to Kindle for the Scribe, the reMarkable app on desktop or phone, or a USB cable and the device folder for Boox. It is the same as adding any other book.
What is in one issue
The difficulty rises inside each kind: three easy, four medium, three hard. The rules of every kind are printed inside the issue, on the page that opens that kind.
The picture is a real page out of Issue 1, exactly as it looks on the tablet. The free sample is 10 puzzles taken from all three difficulty levels, so you can see the hard end before you pay.
What one solution means here
Each puzzle is built by a program that also solves it. The solver is asked to find two solutions; the puzzle is kept only if it finds exactly one, and only if it reached that one by applying rules, never by putting in a number to see whether the grid falls apart later.
The program also checks that no two puzzles in an issue are the same and that no two have the same answer, and it re-derives every clue from the printed answer to catch a drawing mistake. Puzzles that went into an issue are struck off the register, so a later issue cannot repeat them.
Everything is drawn as vector line work, so the lines stay sharp on the tablet screen and on paper. There is no grey, which is what makes a grid hard to read on e-ink.
Questions
In the Stripe customer portal, where you log in with the e-mail address you paid with. You can cancel or change the subscription at any time and it stays active until the end of the period you already paid for. The issues you have already downloaded stay yours.
The e-ink file is 157 x 210 mm, the 3:4 shape of a large e-ink screen, so a page fills the display of a reMarkable 2, a reMarkable Paper Pro, a Kindle Scribe or a Boox reader of that size without bars at the sides. Every issue also comes as A4 and as US Letter, which fit a tablet, a phone or a printer.
Being honest about the limit of that claim: the page sizes and the links are measured in the finished PDF by our own check, but we have not tested an issue on a physical reMarkable, Kindle Scribe or Boox. Nobody here owns one. If a page looks wrong on yours, write to andrej@arling.sk with the device name and we will fix the file.
Yes. Every issue includes an A4 file and a US Letter file with the same 100 puzzles, black and white, made to be printed at 100 percent or actual size rather than fit to page. The solutions are at the back.
No. There is no account, no password and no app of ours. After paying you get an e-mail with download links, and each following issue arrives as another e-mail. What we keep is the e-mail address Stripe gives us for the subscription, so we know where to send the next issue.
The first issue arrives right after you pay, whichever day of the month that is. Every next issue is sent on the first day of the month. If an e-mail does not arrive, write to andrej@arling.sk and we will send the links by hand; we would rather do that than have you wait.
Yes. Stripe e-mails a receipt with VAT for every payment, including every renewal. Stripe Payments Europe, Ltd. is the merchant of record: you buy from Stripe, which issues the document and settles the VAT, and ARLing supplies the files. If you are buying for a company, enter your VAT number in the checkout and the document is made out to the company.
By law, no, and we want to say that before you pay rather than after. Digital content delivered immediately with your consent carries no right of withdrawal: in Slovakia that is section 19 paragraph 1 letter m) of Act No. 108/2024 Coll. on consumer protection, and across the EU it is Article 16 letter m) of Directive 2011/83/EU. Clicking the payment button is that consent, because the first issue is sent at once.
That is the law, not our customer service. The sample is free and comes from all three difficulty levels precisely so you can decide before paying. If a file is broken, a puzzle is wrong, or an issue never arrived, write to andrej@arling.sk and we will fix it or send the money back, because that is a different thing from changing your mind.
No. The puzzle books are ten one off books of a single kind each, made to be printed on paper. Puzzle Post is a subscription, one mixed issue a month, sized for a tablet screen first. The puzzles do not overlap: every puzzle that goes into a book or an issue is struck off the register and never printed again.