Habit Tracker App with Subscription Paywall and Free Trial

The problem with subscription apps built by students

Subscriptions are one of the main ways independent developers earn from mobile apps, and also one of the easiest places to get things wrong. Common failures: a user pays and loses access after reinstalling, restore purchases does nothing, a trial renews without warning, or the paywall hides the price and gets rejected in review. Most student projects never touch payments at all, so graduates who want to ship their own app hit these problems for the first time with real customers.

A habit tracker is a good vehicle because the core is small and well understood. That leaves the team's time for the part that decides whether an app makes money: purchases, entitlements and store compliance.

What already exists and the gap

• Streaks is a paid, Apple-only habit app with Apple Health integration and a one-time price.
• Habitify is cross-platform with analytics and a subscription or lifetime purchase.
• Loop Habit Tracker is free, open source and Android only, with no account and no upsell.

The habit tracker market is crowded, and that is the point: you are not trying to beat these apps on features. The gap this project fills is educational and practical. Few student teams have ever configured a subscription in both stores, tested every renewal and refund path in sandbox, and written a paywall that a reviewer and a user would both call fair. Read the recent one-star reviews of these apps: many complain about lost purchases, surprise renewals or a free tier that shrank. Your app should be the one those reviewers wanted.

What you build

One role, the user, with three layers:

• Free core: create habits, set reminders, tick them off, see streaks and a calendar. Works fully offline, no sign-in required.
• Premium: a clear set of extras such as unlimited habits, detailed statistics, themes and export. Unlocked by a monthly or yearly subscription with a free trial.
• Account and compliance: optional sign-in for sync and cross-device restore, account deletion, and a privacy policy.

Main flows: install and use for free, hit a premium feature, see the paywall, start a trial, get a reminder before the trial ends, convert or cancel, reinstall on a new phone and restore.

The technically interesting part

Entitlements as server truth. The device must never decide on its own that a user is premium. Purchases are validated by the store, reported to RevenueCat or your own backend, and the app asks "what is this user entitled to right now?" on launch and after each purchase event. Handle the awkward states: purchase pending, billing retry, grace period, refunded, and the same Apple or Google account used on two devices. Cache the last known entitlement for offline use, with an expiry, so a user on a plane still gets the features they paid for.

Paywall honesty as a design constraint. Price, renewal period, trial length and how to cancel must be visible before the purchase button. Show your supervisor the App Review Guidelines and Play policy sections you checked and how the paywall meets them.

How to evaluate it

• Sandbox matrix: every scenario in your deliverables list run on both platforms, with expected versus actual entitlement recorded. Target 100 percent pass, with any store-side quirk documented.
• Restore test: reinstall on a second device and restore; record time to regain access.
• Paywall clarity test: show the paywall to 8 to 10 people for five seconds and ask what they would pay, how often, and how to cancel. Report how many answer all three correctly.
• Reminder reliability: local reminders firing on at least three Android brands over a week.
• Store readiness: a checklist of the current store requirements, each ticked with evidence.

Suggested plan

1. Weeks 1 to 2: read low-star reviews of three habit apps; decide the free and premium split.
2. Weeks 3 to 6: build the offline free core with local storage and reminders.
3. Weeks 7 to 9: configure products and trial in both consoles; integrate purchases and entitlements.
4. Weeks 10 to 12: sandbox test matrix, restore, account deletion, privacy policy.
5. Weeks 13 to 15: store listing, closed test with real testers, write-up and demo on real devices.

Path to a product

Publish it. A narrow angle helps: habits for students during exams, for prayer and Quran reading routines, or for recovery from an injury. Keep the free core generous, charge a small yearly subscription with regional pricing, and grow through store search and a few communities that care about the niche. Even modest revenue gives you a live app with real payment data on your CV, which is rarer than another portfolio clone.

Scope warning

Do not build social features, challenges with friends, AI coaching or a web dashboard. Do not implement your own receipt validation server if RevenueCat covers it; if you do, keep it to one platform first. Never buy testers or ratings: it breaks store policies. Store rules and commissions change and differ by region, so quote the current documentation, not a blog post.

Learn what you need on Sefism

• Mobile roadmap : the order to learn a cross-platform framework, local storage and store publishing.
• Mobile cheat sheet : lifecycle, notifications and state management at a glance.
• RevenueCat : subscriptions, trials and entitlements across both stores.
• Google Play Billing : the Android purchase flow and subscription states.
• In-App Purchase (Apple Developer) : StoreKit, sandbox testing and subscription groups.
• App Review Guidelines : what a paywall must show to pass review.

Get help with this idea

This idea is strongest when the paywall is honest and the sandbox log is thorough, not when the habit features are many. Tauseef can help you tighten the scope, choose a stack your team can finish with, and design an evaluation your examiners will respect. If you are new here, create a free account first.

• Discuss this idea with a mentor
• Send a query to Tauseef
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