Start small.
Spend only when you need to.

Your ChatGPT account Already covered

ChatGPT Plus is listed at US$20 a month. Local prices and tax can differ. Codex is included, but its usage is limited. Work in small steps and check the usage screen before buying extra credits.

An API is a way for an app to use an online service. If you later put AI inside your own app, that may have its own bill. It is separate from using Codex to build the app.

Apple’s building tools Free

Xcode and its virtual iPhone are free. A normal Apple Account lets you install an app for personal testing. Free signing expires after seven days, so rebuild and reinstall from Xcode when needed. It is not a way to distribute an app to everyone.

Apple Developer Programme US$99 / year

Needed for TestFlight, the App Store and capabilities such as iCloud and Sign in with Apple. Enrol when you reach that part of the course. Apple shows your local price before you pay. Individuals publish under their legal name. Membership renews annually.

Only on this phone: keep it in the app

Start here if nothing needs to be shared. Apple’s built-in storage has no separate hosting bill. Information can be lost if the app is deleted, so consider export or backup if people will rely on it.

Across one person’s Apple devices: iCloud

iCloud can sync their information using the Apple Account they already have. You need Apple Developer membership to set it up. Private records use the person’s iCloud storage allowance; storage is not unlimited.

Different users and shared records: Supabase

A ready-made service for logins and a shared online store of information, called a database. The free plan includes 50,000 monthly active users, a 500 MB database, 1 GB of file storage and 5 GB of outgoing data. It allows two active projects.

The catch: quiet free projects can pause after a week. That can interrupt a live app. Check the dashboard, backup options and current paid-plan price before people depend on it. The Pro plan starts at US$25 a month, with usage charges possible.

More generous storage, more setup: Cloudflare

Cloudflare can host a small website for free. Its Workers free plan includes 100,000 requests a day for server code. D1, its database, includes 5 GB total storage, five million rows read and 100,000 rows written per day. These are different limits, not one shared allowance.

D1 does not provide a ready-made user login system. It can be a low-cost choice when Codex sets up the extra parts, but the optional account lessons use Supabase to keep the path simpler.

Use a free address first

Your app’s support and privacy pages can live on a free Cloudflare Pages address ending in pages.dev. This is enough to begin. The support lesson walks through uploading the pages without buying a domain.

Buy a name only when it helps

A domain is a name such as yourapp.com. It is optional and usually renewed each year. Cloudflare Registrar sells supported domains at registry cost. Compare both the first year and renewal price, including tax. Domain registration is separate from website hosting.