Challenge Log

1. Introduction

LuckyhanStudio ("we", "us", or "our") operates the Challenge Log application (the "App"). Challenge Log helps you run 30/100/365-day transformation challenges by photographing the same subject over time and turning that timeline into a video. This Privacy Policy explains what happens to your information when you use the App.

By using the App, you agree to the practices described in this Privacy Policy.

2. Local-First: Your Photos Stay On Your Device

Challenge Log is local-first. Your challenges, the photos you take or import, and any video you export are stored only on your device. There is no account and no login, and we do not operate a server that receives, stores, or transmits your photos or videos. We — LuckyhanStudio — never see them.

We recognize that challenge photos can be sensitive: body and weight-loss progress, skin conditions, pregnancy, or photos of a baby or child. These photos never leave your device unless you choose to share an exported video through Android's share sheet to an app of your own choosing (for example, a messaging app or social platform). That sharing action is entirely under your control and happens outside the App.

3. Information We Collect

We do not collect anything that personally identifies you. Because the App has no account system and no backend server, there is no user profile, email address, or photo content for us to receive.

Third-party SDKs used for advertising do collect limited technical data — see Section 5 below.

4. How We Use Information

To display advertising within the App and measure its performance (via Google AdMob)
To obtain and remember your advertising-consent choice where required (via Google UMP)

We do not use any information to build a profile of you, and we have no server-side database of users to use information from in the first place.

5. Advertising and Third-Party SDKs

Google AdMob: The App displays banner, native, interstitial and app-open advertisements through Google AdMob. AdMob and its partners may collect device identifiers and other advertising-related data to serve and measure ads. See Google's Privacy Policy at policies.google.com/privacy and the list of AdMob ad technology partners at support.google.com/admob/answer/6128543.

Google User Messaging Platform (UMP): We use Google's UMP to obtain your consent for personalized advertising where required by law, including in the EEA/UK and other applicable regions. You can review or change your advertising-consent choice at any time from Settings → Privacy options inside the App.

6. Permissions

The App requests each permission only at the moment it is needed, and every permission below is optional except Camera, which is required to take a photo inside the App:

Camera — required to take challenge photos using the in-app ghost-overlay camera.
Photos / Media — optional; requested only when you import an existing photo into a challenge or save an exported video to your device gallery.
Notifications — optional; requested only if you turn on capture reminders.

7. Data Retention

Everything the App creates — challenges, photos, and exported videos — lives on your device and is removed when you delete a challenge or uninstall the App. Because we do not operate a server that stores your content, we hold nothing on our side to retain or delete.

8. Children's Privacy

The App is not directed to children under 13, and we do not knowingly collect personal information from children. (Parents may use the App to document a baby's or child's growth; those photos remain local to the parent's device under the same local-first handling described in Section 2.)

9. Your Rights (GDPR, CCPA and Other Regions)

EEA/UK (GDPR): Because we do not hold your photos, videos, or a personal account on any server, most data-subject requests (access, correction, deletion, objection) have nothing on our side to act on — your content already lives entirely on your device, where you have full control. For advertising data processed by Google AdMob/UMP, you may exercise applicable rights directly via the consent tools in Settings → Privacy options, or by contacting Google.

California (CCPA/CPRA): We do not sell or share personal information, and we do not maintain a database of personal information to disclose, correct, or delete. You may still contact us with any privacy question or request at the email below.

10. Changes to This Policy

We may update this Privacy Policy from time to time. Material changes will be reflected by updating the "Last updated" date at the top of this page.