Ten App Store screenshots that read as one comic

ComicFlow is a comic reader, and until this week its App Store screenshots looked like a settings menu. Ten dark frames, each with a shouted headline, a tag bar and a phone, each one standing on its own. They were accurate. They just didn’t look like anything a person who loves comics would stop scrolling for.

With 3.6, which went live on 12 October, the store page tells one story instead. The panels run across the joins between frames, so the row of screenshots reads left to right like a strip, and a girl with a paper katana walks you through the app as it goes. Her name is Kaede.

Two rows of ten App Store screenshots. Above, the old ComicFlow set: dark frames with bold white headlines and tag bars, each phone separate. Below, the new set: a cream strip with red and black headlines, the frames touching, and the same inked heroine appearing in every frame. — Above, the old set: ten separate frames. Below, the 3.6 set: one strip. The old one opened with the price promise; the new one saves it for the last frame.

Why not just show real comics?

The honest way to show a comic reader is with comics in it. But I can’t put manga I don’t own the rights to on my store page, and a reader full of grey placeholder covers sells nothing. So the screenshots needed a library: covers, pages and titles that look like the real thing and belong to nobody else.

I wrote a brief for eighteen comics in the formats ComicFlow opens: CBR, CBZ, RAR, ZIP and PDF. A ramen stall under a railway bridge. A yōkai train station at night. A fox in a raincoat climbing to a lighthouse, in the clean-line style of a European children’s album. A retro rocket pilot, a badminton sports manga, a cyberpunk hacker, an art-deco detective. The cast is deliberately mixed in age, ethnicity and body type, because the people who read comics are.

Eighteen comic covers in two rows, each in a different style: Paper Ronin, Skyline Couriers, Neon Oni, Lantern Tide, Rally!, The Brass Comet, Midnight Noodle Club, Starfall Academy and Solar Shift above; Spirit Station 9, Mecha Garden, Velvet Detective, Little Fox and the Lighthouse, Kaiju Weather Report, Moonlight Café, Rainline, The Last Bonsai Keeper and Hollow Pines below. — The made-up library. Every cover is AI-generated to my brief. None of these comics exists, and none of them ships in the app.

The art is AI-generated, made with OpenAI’s image model at its highest quality setting. I want to be plain about that, because a page full of convincing manga covers invites the question. I wrote the briefs, picked the results and threw away the misses. The rules in every prompt were the same: nothing that reads as an existing character, franchise, costume or logo; no publisher marks, barcodes or price boxes; and exactly the title I gave, spelled letter by letter. A cover with a misspelled title went straight back.

The whole set, cast and covers and inside pages, came to 58 images over one evening, for about $10 in API costs, counting the ones I threw away.

Kaede

One of those eighteen comics is Paper Ronin, and its heroine became the guide for the whole set. Kaede is Japanese-Brazilian, about 21, with a black bob and one long strand tied in a vermilion paper cord. She carries a satchel full of comics and a katana whose blade is folded white paper, with the creases still showing. The ink is black and white with one spot colour, a vermilion red that sits close to ComicFlow’s own orange.

A character only works across ten frames if she’s the same person in all of them, so she started as a model sheet: front, three-quarter and back, plus three faces. That sheet then went in as the reference image for every pose and every page she appears on.

Four character model sheets of the same young woman in black and white manga ink with red accents, from wide black hakama trousers and a short-sleeved jacket in the first, to a sleeveless top, pleated skirt over shorts and an open jacket in the last. — Four sheets, oldest first. The outfit changed the most. The last one became the reference.

It took four sheets. The first followed my brief to the letter, wide hakama trousers and all. From there the outfit moved the most, towards something sportier that still reads as a modern samurai when she’s the size of a sticker.

Some details took more words than I expected. “A scar through her right eyebrow” can mean either side of the picture, so the prompt says “her RIGHT eyebrow (on the viewer’s left when she faces the viewer)”. And because every prompt describes the sheathed katana at her hip, a pose where she swings the sword can easily end up with two. The leap prompt spells it out: one katana, in her hands, and an empty sheath.

Every prompt for her also carries the same guardrails: she is an adult and clearly reads as one, the art is confident and cool and never sexual, and it suits a general audience. The App Store is a page anyone can open, and I’d rather say that in every prompt than hope for it.

Nine cut-out poses of Kaede with white sticker outlines on a cream background: leaping with the katana raised, slashing with paper scraps flying, reading cross-legged, pointing, asleep against a stack of manga, staggering under a pile of comics, winking with a two-finger salute, riding a giant paper crane, and pressing a red seal stamp forward. — The nine poses, cut out with a white sticker edge so they sit on top of the phone in each frame.

Ten beats, one strip

Each frame is one feature and one beat of the story, and Kaede’s pose is the joke for that feature. She leaps past the library. She slashes through a list of files on the Convert screen. She sits down to read. She points at the right-to-left switch on a manga page. She falls asleep against a stack of manga, next to the card that brings you back to the same page. She staggers under a pile of comics for Wi-Fi Upload, rides a folded paper crane to an e-reader, holds out a seal stamp beside the shelf locked with Face ID, and winks on the last frame: one purchase, no subscription, ever.

The part I like most is the joins. A panel lifted out of one screen hangs over the edge into the next, and the strip only lines up if the frames are shown touching, the way the store shows them in a row.

Three App Store frames side by side without gaps: Open. Read. Done. with a Skyline Couriers page, Right to left, the way manga is drawn with a Spirit Station 9 page, and Fell asleep? Wake up on the same page with a Continue Reading card. Kaede appears reading, pointing and asleep. — Frames three to five. You can scroll through the whole strip on the ComicFlow page.

Everything inside the phones is real. The covers and pages are the made-up library, but the screens are ComicFlow itself, running in the simulator, not mock-ups. Frames seven to nine show Pro features, and they say so.

Real screens, eighteen times over

Getting real screens means getting the library into the app, in the same order, every time. A script erases the simulator and imports the eighteen comics through ComicFlow’s own Inbox, one launch per file, so the cover grid always comes out in the same order.

Then the app has to be put into the right state for each frame. The UI tests that do this normally find buttons by their label, and that breaks the moment the label is German or Thai. In 14 of the 18 languages the tests couldn’t find the controls they needed: the right-to-left toggle, the Sources row, the close button on the continue-reading card. So four small launch flags set those states directly for the screenshot run, and the tests stop guessing.

One flag found a real problem. The Wi-Fi Upload screen shows the device’s name, so for the screenshots it reads kaedes-iphone.local, or kaedes-ipad.local on iPad. My first version picked between the two with the device idiom. ComicFlow has a unit test that fails if the idiom appears anywhere in its sources, added after the iPhone Duo showed me the app assumed every iPhone was the same shape. It failed, as it should, and the name now comes from the device model.

The first App Store frame in English, German and Japanese side by side: All your comics and manga, one home; Alle Comics und Manga, an einem Ort; and the Japanese headline. The app interface in each phone is in the same language as the headline. — Frame one in English, German and Japanese. The screens inside are captured in each language, not just the headline.

The frames themselves are plain HTML and CSS, rendered by headless Chrome at the exact pixel sizes the App Store wants. A check fails the export if any translated headline doesn’t fit its box. Another script finds where each lifted-out panel sits in the translated layout and moves the callout to match, because a German button is rarely where the English one was. Twice, a Chrome render froze at zero CPU and held up the whole run for an hour, so every render now times out after two minutes and tries again.

Each language gets four sets: the 6.3-inch and 6.9-inch iPhones, the 13-inch iPad and the inner screen of iPhone Duo, ten frames each. That’s 40 images per language and 720 in all.

The Open. Read. Done. frame twice: on iPad in portrait, with a Skyline Couriers page and one panel lifted out of it, and on the iPhone Duo inner screen in landscape, with the cover and a page side by side. Kaede sits cross-legged reading in both. — The same beat on the iPad and on the iPhone Duo's inner screen. Each device gets its own layout rather than a stretched iPhone frame.

Uploading 720 screenshots

I normally upload screenshots with fastlane. This time it couldn’t do the job: it has no screenshot type for iPhone Duo yet, and its overwrite option deletes the old screenshots before uploading the new ones. On 10 October, App Store Connect was having trouble deleting, and that combination stalled with nothing uploaded. So the set went up with the asc command-line tool instead, one device type at a time, skipping anything already there.

Then I checked all 72 sets through the API: ten screenshots in each, a checksum matching my local file in every slot, every one fully processed. I didn’t trust the website for this. During the outage it showed sets as deleted that the API still had.

What I’d tell myself before starting

Make the character sheet first, and don’t move on until it’s right. Every pose and page leans on it. Fixing her outfit after nine poses would have meant nine more images.
Write the obvious down. Which eyebrow, how many swords, how old she is, what she isn’t. The model doesn’t share my assumptions.
Never let a test look for a button by its label. Not if the screenshots ship in 18 languages.
Be upfront about what’s made up. The titles in these screenshots don’t exist, and they don’t come with the app. Your library starts with your own files, and the page says so.

Whether the new set turns more store visits into downloads, I’ll only know after a few weeks of App Store data. Either way, I wanted the store page to feel like opening a comic, and now it does.