JC STUDIO · STICKER CALENDARPrivacy Policy
Effective: 2026-10-30
1. Operator and scope
JC Studio provides Sticker Calendar (스티커 달력, formerly Retro Calendar), Android package com.jcstudio.retrocalendar. Contact: whdcjf8172@gmail.com. This policy covers the app and this information website.
2. Your local records
Dated tasks, completion status, notes, manually selected weather, anniversaries (birthdays, memorial days and the like), the stickers, tapes, stamps, labels and pen drawings you place on pages and where they sit, and preferences are stored in SQLite on your device. There is no account, developer-server sync, location tracking or contact collection. Weather is not fetched from a forecast API. JC Studio does not receive your diary contents, and tasks and notes are not sent as ad-targeting data.
Usage statistics: when the app starts (the first launch of a day and later restarts) it sends a random install number created at installation (not a device ID or advertising ID), a launch number, the app version, the device language setting and the operating system (Android) to the developer's Supabase server to count installs and launches. The server records the date and time. Diary contents such as tasks, notes, decorations, photos and calendar events, accounts, location and advertising IDs are not sent, and the counts are not used for advertising or payment decisions. The install number is not linked to a name, email or device identifier, so the developer cannot pick out a particular person's records. The counts are kept for statistics; uninstalling stops them, and clearing app data or reinstalling creates a new install number. This applies from the app update that adds usage statistics.
When public holidays are turned on, the app requests the holiday list from the Nager.Date service (date.nager.at) with only the year and the selected country code, stores the list on your device and downloads it again after two weeks. The request contains none of your calendar records; as with any internet request, the service may process your IP address. You can change the country or turn holidays off under “Public holidays” in Settings.
If you use “Make a sticker from your photo”, the Android photo picker hands the app only the one photo you choose; the app saves a copy in its private storage to show it as a sticker. The app does not request access to your whole photo library, does not send photos to JC Studio or for advertising, and does not put them in backups. Removing the photo sticker or clearing app data deletes the copy.
“Share as a picture” turns the page on screen (its decorations, your to-dos and notes, and any phone calendar events shown) into an image and previews it; only when you tap Share is it handed, through the Android share sheet, to the app you pick. Neither the app nor JC Studio keeps or sends the image otherwise, and what happens after sharing follows the chosen app's terms. The image is kept in the app's temporary folder and deleted at the next share.
If you turn on “Daily reminder” in Settings, the app asks for Android's notification permission, keeps the reminder times and words for the next 14 days (holiday names included) on the device only, and the device shows the notification at the time you chose. No reminder comes on a day you have already opened the app. Reminders are never sent to JC Studio servers or advertisers; turn them off in Settings or withdraw the permission in Android settings.
If you turn on “Phone calendars” in Settings, the app uses the Android calendar permission (read and write) to read the events of the calendars synced on your device, such as Google or Samsung, and print them on its pages, and it writes the events you add in the app to the calendar you choose. Events are read on the device only to display them; the app does not store them separately or put them in backups, and does not send them to JC Studio or for advertising. Events you add are saved through that calendar's own account sync (for example your Google account) under its provider's terms. If you turn on “Also add to the phone calendar every year” for an anniversary, the app writes it as all-day events for this year and the next four into the calendar you chose and keeps adding as the years go by; when you change or delete the anniversary, it changes or removes only the upcoming events it wrote. Lunar dates and solar terms are calculated on the device without any request. You can turn this off in Settings or withdraw the permission in Android settings at any time.
3. Advertising, purchases and choices
The app shows Google AdMob ads. There is no banner: a frequency-limited full-screen ad may appear when you put a decorating session away, from the second session of a day, and a rewarded ad (one ad opens the Plus decorations until midnight) plays only when you choose it in the Plus window. The Google Mobile Ads SDK may collect and share device or account identifiers, including advertising IDs, IP addresses (which can indicate a general area), app and ad interactions, and diagnostics for ad delivery, measurement, fraud prevention and reliability. We have no separate analytics SDK (the usage statistics in section 2 are install and launch counts the app sends to our own server); the advertising SDK includes its own measurement. SDK transmissions use TLS.
Sticker Calendar Plus (paid): when you buy or restore it, Google Play processes the payment; only Google Play handles card numbers and other payment details, never the app or the developer. To verify and restore purchases, the RevenueCat SDK processes an anonymous customer ID created at random for each install, product and transaction identifiers, the purchase receipt and the subscription status (expiry and renewal). The day opened by a rewarded ad and the last known Plus status are stored on the device only. While Plus is active the advertising SDK is not started.
Google UMP presents applicable choices in the EEA, United Kingdom, Switzerland and other relevant regions. We request ads only when the SDK permits it. Processing requiring consent relies on your consent. You may use the calendar without consenting. Where required, Settings provides “Ad privacy choices” to change or withdraw your choices. Declining personalization may still allow limited ads according to the SDK's eligibility rules. Applicable US state privacy options are also handled through UMP. Android settings let you reset or delete your advertising ID.
4. Retention, deletion and backups
Records remain on the device until you delete entries, clear all records or clear app data. Uninstalling may erase local data; we cannot restore it from a server. Exported backups remain separately in your chosen location. The app does not automatically upload backups. If you choose a cloud document provider, that provider's terms apply. Confirmed restoration replaces existing records. Android automatic app backup is disabled.
Ad impression timestamps are stored separately on the device for frequency limits, evaluated over the most recent 24 hours. Diary deletion or restoration does not reset these limits. Google controls retention and deletion of SDK-collected data and UMP consent information under its policies and controls.
5. Providers, international processing and this website
Google and providers involved in advertising may process data outside your country. Applicable providers and purposes are described in the consent interface and Google's policies. Cloudflare Pages hosts this website and may process IP addresses and request details for delivery, security and operations. We add no analytics scripts, forms, advertising or first-party cookies to this site. If you email support, we use your address and message to respond and delete them when no longer needed.
6. Your rights and protection
Depending on applicable law, you may request access, correction, deletion, restriction, portability, consent withdrawal or applicable opt-outs concerning targeted advertising, sale or sharing. Manage local records in the app and advertising choices through app settings, Android or Google tools; contact us for assistance. Where available, you may complain to your local supervisory authority. The app is not designed for children and does not knowingly request children's personal information. Contact us with any related concern.
7. Changes and provider policies
We update this policy and its effective date when data handling changes. Material changes will be announced in the app or on this page.
8. International transfers
Google LLC (United States, privacy contact form support.google.com/policies/contact/general_privacy_form) — IP address and approximate location derived from it, device identifiers such as the advertising ID, app and ad interactions, diagnostics / when ads are requested (only where permitted in regions that need consent) / to deliver and measure ads and prevent fraud / kept under Google's policies. Supabase, Inc. (United States company; database in the Seoul, Korea region; privacy@supabase.io) — random install number and launch number, app version, device language setting, operating system / when the app starts / to count installs and launches / kept while the app service is operated. Google LLC (Google Play billing) — purchase history and payment details / when you buy or restore Plus / to process payment / kept under Google's policies. RevenueCat, Inc. (United States, privacy@revenuecat.com) — anonymous customer ID, product and transaction identifiers, purchase receipt, subscription status / when the app starts and when you buy or restore Plus / to verify and restore purchases / kept under RevenueCat's policy. Cloudflare, Inc. (United States, privacyquestions@cloudflare.com) — IP address and technical request logs when you open this website / when the website is opened / to deliver and secure the pages / kept under Cloudflare's policies. Everything is sent over encrypted connections (HTTPS) each time the feature is used. If you do not want these transfers you can refuse the ad privacy choices or delete the app; refusing the transfers needed for ads may limit free use, but the core features work without ads or an internet connection.
9. Privacy officer
Jongcheol Lee (owner), whdcjf8172@gmail.com. We reply to access, correction, deletion and suspension requests within 10 days.
10. Remedies
You can also contact the Personal Information Dispute Mediation Committee (1833-6972, www.kopico.go.kr), the Privacy Infringement Report Center (118, privacy.kisa.or.kr), the Supreme Prosecutors' Office cyber crime unit (1301, www.spo.go.kr) or the National Police Agency cyber bureau (182, ecrm.police.go.kr).
11. Changes
October 30, 2026: described the ads (no banner, a full-screen ad when decorating is put away, rewarded ads you choose), Sticker Calendar Plus purchases (Google Play, RevenueCat) and the daily reminder. October 19, 2026: added usage statistics (install and launch counts with a random install number). October 17, 2026: renamed the app to Sticker Calendar and described decorations, photo stickers and sharing a page as a picture. October 16, 2026: added privacy officer, international transfers and remedies.