A puzzle about what you can see from the edge
Every row and column holds each height once. The number on an edge is how many towers you can see standing there — a taller tower hides every shorter one behind it.
One rule
A four by four uses 1 to 4, a five by five uses 1 to 5. Every row and every column holds each of them exactly once, which turns a row from a guess into a short list of possibilities.
A tower is visible if it is taller than everything between you and it, so a 6 at the near end hides the whole row behind it and the count there is 1. The number on the edge is that count, and it is the only rule in the game.
Some edges carry no number at all. Those counts are yours to work out from the rest of the board, and the fewer numbers are printed the longer the chain of reasoning has to be.
Three chapters
Four by four, and the edge numbers do most of the work. Start by asking which row could possibly begin with a 4.
4×4 · 7–12 cluesFive by five, and some edges go blank. A blank edge is not a missing clue — it is a clue that says the count is yours to work out.
5×5 · 9–16 cluesSix by six, half the edges blank, and a few towers already standing. The built ones are the cheapest information on the board.
6×6 · 16–22 clues · 3–6 builtWhat it does not do
No in-app purchases, no advertising, no energy meter, no streak to keep. The whole game is in the download.
No account, no analytics, no third-party code, and no network requests at all. It works with the phone in flight mode.
Undo, erase and restart are always there and always free. Nothing can be spoiled so badly that starting again is a loss.
The small print, in plain words
Last updated 2 November 2026
Spirewise does not collect anything about you.
There is no account, no sign-in, and no profile. The game makes no network requests of any kind, so nothing you do can leave your device even in principle — not a score, not a solved skyline, not a crash report.
Everything the game remembers is stored on this device, in the app's own storage: which skylines you have answered, how many stars you earned, and whether you left the sound or the haptics switched off. Deleting the app deletes all of it, permanently. There is no server copy to ask us to remove, because there is no server.
The game contains no advertising, no analytics, no tracking, and no third-party code of any kind. It does not ask for your name, your email, your location, your contacts, your photos, or access to your microphone or camera.
If you are a parent: there is nothing here to buy, nothing to sign up for, and no way for your child to talk to anyone through this app. The App Store age rating reflects that.
Questions about this policy can be sent to the support address on the App Store listing, and will be answered.
Spirewise is licensed, not sold. Your purchase grants you a personal, non-transferable right to use this app on Apple devices that you own or control, as set out in the Apple Media Services Terms and Conditions. It does not grant you ownership of the app, its artwork, its level design, or its code.
The game is provided as it is. It has been tested on every supported iPhone and simulator, and it is deliberately small and self-contained, but no warranty is offered that it will run without interruption on every possible configuration.
Every skyline that ships was checked by the game's own solver before release: exactly one arrangement of heights satisfies the numbers printed around it, so every level can be reasoned to a finish without guessing. If you find one that cannot, that is a bug and we would like to hear about it.
Progress lives on your device. If you delete the app, or lose the device, the skylines you have answered are gone; there is no cloud backup because there is no cloud. This is a deliberate design choice, not an oversight.
You may not decompile, resell, redistribute, or republish the app or any part of it. You may not use its level data or artwork in another product.
Nothing in these terms limits rights you have under the consumer law of your country of residence, and nothing here claims ownership of anything Apple's own terms already govern.