K-Tile — Privacy Policy (English)

Effective 2026-10-06 · v2.0 · The Korean text above is the original; this English version has the same content.

A. Who we are

K-Tile (store name “K-Tile: Space Journey”, package com.softback.layerpuzzle) is operated by Softback (소프트백), represented by Baek Young-jon. Business registration no. 416-31-65901 · mail-order business report no. 2026-화성동탄-2967 · 99 Dongtanjungang-ro, Dongtan-gu, Hwaseong-si, Gyeonggi-do, Republic of Korea · hosting provider: Cloudflare, Inc. · Privacy officer: Baek Young-jon, softback.help@gmail.com.

A-1. What we do not collect, and app permissions

We do not collect your name, gender, phone number, precise location, contacts, call logs, SMS, photos, camera, microphone, files or installed-app lists, and we use no third-party analytics. Your year and month of birth are asked on first launch but are not stored or sent (§B-1). Email is stored only if you sign in (§I).

The only permission the app asks you for is notifications (Android 13 and later); you can refuse it and still play. The other permissions are normal ones that Android grants automatically: internet and network state (the traffic listed above), notification scheduling after reboot (§H), Google Play billing (§E), the advertising ID and related ad services (§C), and account credentials for the Google sign-in window (§I) — the same library also adds biometric permissions, but the app does not use biometrics. There is no location, contacts, camera, microphone or storage permission.

B. Stored on your device only

Progress and stars, coins, hearts, items, owned packs and skins, learning records, settings, cosmetic choices, a 12-character random ID (§H), and your age band (§B-1). Uninstalling the app deletes all of this and we cannot restore it — we keep no backup of game progress, and signing in does not move progress to your account. Items bought with real money (remove ads, time spirit, defense tower, hearts unlimited subscription, full edition, language pack) come back automatically on the same Google account. Coin bundles and anything bought with coins do not come back.

B-1. Year and month of birth — asked once, kept as an age band on your device

The first time you open the app (or once after updating), a screen asks for your year and month of birth — whether or not you ever sign in. We ask because the rules differ by age: Google does not allow personalised ads for anyone under 18, Google Play asks apps to treat users of unknown age like children, and Korean law requires guardian consent to process the personal data of children under 14.

• What is kept: only one of “18 or over / 14–17 / under 14” and the month the band changes next, on your device. Your year and month of birth themselves are not stored.
• It is not sent: for users under 18 the “month the band changes” can be counted back to the birth month, so it never leaves your device — not to our server and not to Google. When you sign in, the only thing sent is a single yes/no: “14 or older”.
• We do not ask for the day. In your birth month we treat your birthday as not yet reached.
• You cannot re-enter it later; clearing the app's data asks again (and also deletes your game progress).
• Under 14: no ads are shown (the ads module is not started and there are no ad buttons) and the sign-in button does not appear. 14–17: non-personalised ads only. 18 or over: personalised ads may be shown (§C).

C. Advertising (Google AdMob)

The app is free and funded by ads and optional purchases. An interstitial ad appears after every 4th level (never during play); rewarded ads play only when you tap a button (extra heart, double reward, extra spin). Users under 14 see no ads.

To serve and measure ads, Google collects the advertising ID (AAID), device and app information, IP address and diagnostics (whether an ad loaded, errors, response times) through the ads module in the app, under the Google Privacy Policy and How Google uses information from partner apps. This data does not reach our server; we see only aggregate counts. The app uses no cookies.

Personalised ads are possible only if you said you are 18 or over. Under 18 or age unknown, every ad request is marked as non-personalised. For 18 or over we do not add that mark, and whether ads are actually personalised depends on where you are and what you chose: in the EEA, UK and Switzerland only if you consent in the dialog below; in some US states Google shows an opt-out dialog under those states' laws; elsewhere, unless you delete your advertising ID or opt out of ad personalisation in Android Settings → Privacy (or Google) → Ads. Even non-personalised ads may use the data above for fraud prevention, frequency capping and coarse (IP-based) location. The “Remove Ads” purchase stops the interstitial ads; rewarded ads you choose to watch remain available.

D. Text-to-speech

When a word is read aloud, that single word (e.g. dog) is passed to your device's speech engine. It never passes through our servers. Your device's engine may use the network under its own provider's policy. You can turn this off in settings.

E. Payments

Optional purchases: with real money — coin bundles, remove ads, time spirit, hearts unlimited (monthly or weekly subscription), defense tower, full edition and a language pack (currently German); with in-game coins — word packs, map packs, items, outfits, poses and tile skins. All real-money purchases go through Google Play Billing; we never receive card, bank or billing-address details.

To confirm a purchase is genuine, the app sends our server the product id, the purchase type and the purchase token right after payment. The server asks the Google Play Developer API whether it is real and decides the amount granted. It stores the purchase token, product id, type, amount granted and verification time, plus Google's order id, purchase time, purchase state and region code. No name, email or account is included, and the record is not linked to a signed-in account. It is kept for 5 years (Korean e-commerce record-keeping law and refund disputes), then deleted automatically.

F. Children

The app is intended for users aged 14 and over. Google Play has no “14 and over” bracket, so the 13–15 bracket was selected as well; that is why the app asks your year and month of birth on first launch (§B-1). Users under 14 see no ads (the ads module is not started) and no sign-in button, so no email or similar data is exchanged. We do not knowingly collect personal information from children under 14. Parents with concerns can contact us (§G).

G. Your rights and contact

You (or your legal guardian) may request access, correction, deletion or suspension of processing, and may withdraw consent. Device data can be erased at once by clearing the app's data. If you signed in, you can delete your account yourself (in the app: Settings → Account → Delete account; outside the app: k-tile.pages.dev/en/account/delete), and the deletion is immediate. Purchase records can be checked with your Google Play order id, but must be kept for 5 years by law. For anything else, email softback.help@gmail.com; we reply within 10 days. Korean residents may also contact the Personal Information Infringement Report Center (privacy.kisa.or.kr, 118) or the Personal Information Dispute Mediation Committee (www.kopico.go.kr, 1833-6972).

When you delete your account, the Google link, email, sessions and account are removed at once. Two things remain: one irreversible hash of the Google identifier mixed with a server secret (1 year, to recognise a re-join; it does not block re-joining) and sign-in audit rows (90 days, with no email or identifier). Game progress lives on your device and is not affected.

H. Server features

• Random ID and invites. The app creates a 12-character random ID on first launch. It is unrelated to your name, device serial or account, but because it keeps pointing to the same device we treat it as pseudonymous personal data under the GDPR. Each time the app starts, this ID is sent to check whether an invite gift has arrived. If a friend installs the app through your invite link, their app sends your ID and theirs so you can receive a gift. Invite records are deleted 30 days after the gift (1 year if never collected). Clearing the app's data creates a new ID that we cannot link to the old one.
• Ranking. After each cleared level, one score number is sent — with no ID, advertising ID or account — to show “top X% in your country”. Only aggregate counts per country and score band are kept.
• Notifications. Reminders are scheduled locally on your device (no push token, no server); only between 09:00 and 21:00, at most once a day, and at most twice (after 3 and 7 days) when you are away. They can be turned off in settings.
• Word error reports. Only when you send one: word id, language, reason (one of four) and app version — there is no free-text field and no identifier. Kept for 1 year.
• New packs. On start the app checks for new word packs, map packs and tile skins, and downloads card pictures for word packs you bought from k-tile.pages.dev. Nothing is sent; Cloudflare processes your IP address only to deliver the files.
• Returning-player gift and refund check. When earlier purchases are restored, the Google purchase token is sent to check whether a 500-coin welcome gift was already given and whether the purchase was refunded (refunded items are switched off). Kept for 5 years.
• Visit count. Once a day: the random ID, the date and a two-letter country code (no time, no activity). Deleted 400 days after your last visit. No third-party analytics run in the app; a Facebook login SDK is present in the build for future use but does not start and sends nothing.
• Coupons. When you enter a coupon code, the code and the random ID are sent; afterwards the ID is sent on start to check the remaining period. The server keeps only an irreversible hash of the code, which device used it and when. Used coupons are deleted after 1 year; unused expired ones after 90 days.
• Public word review page (ktile-api.softbackdev.workers.dev/words, a web page, not the app): suggestions carry a word id, language, suggested meaning and an optional reason — no name or account, no cookies. The IP address is stored only as the first 16 characters of a SHA-256 hash for rate limiting and deleted after 1 day.

I. Google sign-in — optional

Signing in is optional; the whole game works without it, and signing in does not move your progress to the cloud. When you sign in, the app sends the ID token issued by Google, a single yes/no “14 or older” from the age screen, and the random ID. Your password never reaches us.

• We store an account id (random), the link to your Google account identifier, your verified email address (only if Google says it is verified), the time of the age confirmation and of the last sign-in.
• Session tokens are stored only as hashes for 7 days; sign-in audit rows (time and type of event, no email or identifier) for 90 days.
• We do not receive your name, profile picture or date of birth.

J. Versus matches

Entering the arena next to the main route is using this feature; the tutorial's last step plays one arena level. If you do not start an arena level, nothing in this section is sent. The app sends seven skill numbers (words learned without hints per word pack), the level, the time rule, the layout number and a two-letter country code — no word list, random ID, account or advertising ID. When you clear an arena level, its progress curve (seconds, pair count, which two cells) is kept as a future opponent: up to the latest 30 per level, rule and country, and no longer than 90 days. If no opponent is found you play against the device, and the screen says so.

For real-time matching the server issues a temporary ticket for one match only. The waiting row (vs_queue: ticket, level, time rule, skill numbers, country, time) is deleted when the match ends or you stop searching, and in any case after 3 minutes of waiting or 30 minutes without contact during a match. Leaving voluntarily leaves only a hash of the ticket for 10 seconds. The ticket does not identify you. There is no chat.

K. Where data is processed

We do not sell or provide personal data to third parties. Our server, database and website run on Cloudflare, Inc. (United States and other countries where Cloudflare operates) as a processor; Cloudflare does not use the data for its own purposes. Google LLC (United States and other countries) processes advertising data through AdMob, and handles payments and sign-in directly on its own screens. Data is transferred over HTTPS when the app is used.

L. Security

We collect as little as possible; all traffic to our server uses HTTPS; session tokens, coupon codes, deleted-account traces and review-page IP addresses are stored only in irreversible form; device data is isolated by Android; the operator console is protected by a key sent only in a request header; to stop request flooding some requests are counted per IP address for a short time without storing the address; expired records are deleted automatically every day; the app is distributed only through Google Play.

M. Changes

If the law or the app changes, this policy changes too and the new text and effective date are posted on this page. Previous versions are available on request.