Privacy Policy
Effective 2 November 2026
This policy explains what data the DevPrep app (formerly Developer Helper, iPhone, iPad and Mac) and the website iosdevprep.com collect, why, and what you can do about it. DevPrep is developed by Aliaksei Yelin, an individual developer ("we"). Contact: leshaelin@gmail.com.
In short: DevPrep has no accounts. We do not ask for your name, e-mail or phone number. Your progress stays on your device and in your own iCloud. We use a few third-party services for analytics, crash reports, subscriptions and push notifications. Advertising measurement by Meta happens only if you tap "Allow" in Apple's tracking prompt.
What the app collects
| Data | Why | Who processes it |
|---|---|---|
| Usage events (for example "challenge solved", "paywall shown"), app version, device model, OS version, language, country derived from IP, a random app-instance ID | To understand which features help people prepare and where they get stuck | Google Analytics for Firebase |
| Crash reports (stack trace, device model, OS version) | To find and fix crashes | Firebase Crashlytics |
| A random customer ID, purchase and subscription history, App Store receipts | To unlock PRO, restore purchases and run free trials | RevenueCat, Apple |
| Apple Ads attribution token | To see which App Store search ads led to installs and purchases | Apple, RevenueCat |
| Push notification token and the news topics you follow | To send the daily reminder and iOS news you turned on | Firebase Cloud Messaging, Apple |
| Content error reports and interview reports you choose to send (the text you type, the item ID, app language and version) | To fix mistakes in answers and keep company interview plans up to date | Cloud Firestore (Google) |
| Anonymous counts of first attempts per challenge (attempted / correct), not linked to you | To spot broken or mis-rated challenges | Cloud Firestore (Google) |
| Only if you allow tracking: install and launch events and an anonymous Meta ID; trial and purchase events sent through RevenueCat | To measure our ads on Facebook and Instagram | Meta Platforms |
Before you allow tracking, the Meta SDK is not started and sends nothing; installs are counted only through Apple's privacy-preserving SKAdNetwork. You can change your choice at any time in Settings → Privacy & Security → Tracking.
What stays with you
- Progress, bookmarks, notes and settings are stored on your device and synced through your iCloud account (Apple's iCloud key-value storage). We cannot see them.
- On-device AI (answer review, hints, the AI interview) runs entirely on your device using Apple's on-device model. Your answers are never sent to us or anyone else.
- Translation of news articles uses Apple's on-device Translation framework.
Website
iosdevprep.com is a static site hosted on Firebase Hosting. The hosting provider keeps standard server logs (IP address, browser, pages requested) for security and reliability. The site sets no cookies and has no analytics or ads.
Legal bases (EEA/UK users)
Analytics, crash reports and the anonymous challenge statistics rely on our legitimate interest in keeping the app working and improving it. Subscriptions rely on performing our contract with you. Reports you send rely on your consent. Advertising measurement by Meta relies on your consent given in the tracking prompt.
Retention
Analytics data is kept no longer than 14 months (the Google Analytics retention setting), crash reports for 90 days. Purchase records are kept as long as needed for subscriptions, refunds and accounting. Content and interview reports are kept while they are needed to improve the content; you can ask us to delete yours.
Your choices and rights
- Turn off tracking in Settings → Privacy & Security → Tracking, and notifications in Settings → Notifications → DevPrep.
- Deleting the app removes its local data; progress in iCloud can be removed in Settings → [your name] → iCloud → Manage Storage.
- Depending on where you live, you may have the right to access, correct, delete or export your data, and to object to processing. Because we have no accounts, write to leshaelin@gmail.com and, if the request concerns purchases, include the order ID from Apple's purchase receipt e-mail. You can also complain to your local data protection authority.
Children
DevPrep is meant for software developers and is not directed at children under 13. We do not knowingly collect data from children.
Data transfers and sharing
Our service providers may process data outside your country, including in the United States, under their own safeguards. We do not sell personal data and do not share it with anyone except the providers listed above and where required by law.
Changes
We will update this page when the app's data practices change and show the new effective date above.