Step 2 of 5 · about 15 minutes
What you need
By the endYou have everything on this list, or you know exactly what is still missing.
Here is the complete list. Most people already own the expensive parts. The guide works with a Mac or a Windows PC, and with an iPhone, an Android phone, or both. Pick yours at the top of this page, and the list below matches your choice.
A computer
Apple's app-building tool, called Xcode, runs only on a Mac. Any Mac Apple sells today works: MacBook Air, MacBook Pro, iMac, Mac mini or Mac Studio. An iPad does not work.
The Mac needs an Apple chip, also called Apple silicon: M1, M2, M3, M4 or newer. Macs sold since late 2020 mostly have one. The newest Xcode, Xcode 27.1, requires macOS 26.6 (Tahoe) or newer, on a Mac with an Apple chip (M1 or newer). Older Macs with Intel chips can run slightly older tools for a while, but they are a dead end for this guide.
To check which chip your Mac has (skip this if you have never used a Mac; Part 1 shows you how):
- Click the black apple shape at the top-left corner of the screen.
- Click About This Mac.
- Look for a line that says Chip. If it says Processor instead, the Mac has an Intel chip.
If you are buying a Mac, the cheapest current MacBook Air or Mac mini is enough. Choose more storage if you can afford it. Building tools take a lot of room.
A Windows PC works for the whole guide: a laptop, a desktop tower, or an all-in-one. It needs:
- Windows 11. Windows 10 still runs Claude's app (it needs Windows 10 or newer), but Microsoft stopped its free security updates on October 14, 2025, so plan to move on from it.
- 8 GB of memory (RAM), and 16 GB is better. Windows itself needs 4 GB; the building tools want more.
- At least 50 GB of free space. Part 1 shows how to check and how to free some.
To see what you have (skip this if you have never used a PC; Part 1 shows you how): click the Start button, click Settings, then System, then About. Installed RAM shows the memory. Under Windows specifications, Edition shows which Windows you have.
Here is how a PC makes an iPhone app, since Apple's own building tool does not run on Windows. The toolkit this guide uses comes with an online build service. Your PC sends your app's files to the service, a Mac in the service's data center turns them into the iPhone version, and the finished app comes back to your phone. You test on your real iPhone. There is no pretend iPhone on a PC, as there is on a Mac, so your own phone is your test screen from day one. Android versions are built the same way, or on the PC itself. The same service also sends your finished app to Apple and Google when you launch.
The service has a free level: up to 15 iPhone builds and 15 Android builds a month on the free plan, in a slower, lower-priority queue than the paid plans (your build waits behind paying customers). That is plenty while you learn, because most of your testing happens without a build at all (Part 5 explains). When you need more, the lowest paid plan is $19 a month plus any use beyond the $45 of build credit it includes, one extra iPhone build is about $2 for one iPhone build on a standard build machine ($4 on a larger one), and one extra Android build is about $1 for one Android build on a standard build machine ($2 on a larger one). Check the current numbers at expo.dev/pricing.
The simple alternative, if you would rather have Apple's tools on your desk: buy a Mac mini, from about $799, and follow the Mac path of this guide. It is a small box that plugs into any screen, keyboard and mouse.
Advanced
For Windows PC readers only. This is optional, and harder than the main Windows path, which does not need it: renting a Mac online means working inside a second computer through a window on your PC.
Rent a Mac online. Some companies rent out real Macs that sit in their data center. You sign in from your PC with a remote-desktop app, and the Mac's screen appears in a window. Everything on it is real: Xcode, the pretend iPhone for testing, the Mac path of this guide. It helps if you want Apple's own tools without buying a Mac, for example to try the pretend iPhone for an afternoon.
Roughly what it costs: a shared Mac is about $25 to $30 a month for a shared Mac (one user account on a Mac other people also use); pay-as-you-go is about $1 an hour, bought as a block of prepaid hours that expires after 60 days without a sign-in; a Mac that is yours alone is about $60 to $165 a month for a Mac that is yours alone, depending on how new it is. Well-known providers include MacinCloud, MacStadium and Amazon's EC2 Mac service. These are options, not a recommendation; compare their current pages before paying anything.
Why it is harder: everything happens inside a window inside your PC, which is confusing at first. The screen lags, and large downloads like Xcode take as long there as at home. Shared plans do not let you install everything. And you are signing into accounts on a computer you do not own: never save your personal passwords on it, sign out when you finish, and keep your paper list at home. The guide's Windows path builds the iPhone version with the online build service instead, which needs none of this.
A phone
Your own phone is fine. You will install your app on it, so it should be a phone you carry every day.
It needs to run iOS 17 or newer (roughly any iPhone from 2018 on). The free testing app you install in Part 5 needs iOS 16.4 or newer. The Claude app for iPhone, which Part 2 installs, needs iOS 18 or newer, so aim for that. It is optional: if your iPhone is older, the Claude app on your computer is enough.
Almost any recent Android phone works. The free testing app you install in Part 5 needs Android 7 or newer (check the 'Requires Android' line on the Expo Go page in Google Play). Part 1 shows where to find your phone's version.
If you have both kinds of phone, choose both at the top of the page. One app runs on both, and you can test on each.
Internet
A home Wi-Fi connection. You will download several large files, so a steady connection matters more than a fast one.
An email address
One email address that is yours and that you can open on your computer. Every account in this guide uses it. Part 1 helps you set one up if you need to.
Store accounts
An Apple Account (older name: Apple ID) is the free account you use for the App Store and iCloud. If you use an iPhone, you almost certainly have one. If not, Apple's page How to create a new Apple Account walks you through it. It must have two-step sign-in turned on. Part 1 checks this with you. You need it on a Windows PC too: Apple's developer pages are websites, and they work from any computer.
A Google account is the free account your phone uses for Google Play. It is the Gmail address the phone was set up with. If you do not have one, Part 1 shows how to make a Gmail address, which is the same thing.
Services you'll add along the way
Your computer and your phone are enough for the first screen. A finished app also leans on a few outside services. None of them is needed yet. The guide tells you when, and Part 9 compares your options for each one. Most have a free level that covers a new app.
- A server and a database: keep accounts and saved data in one place, so the app works on a new phone too. Part 8.
- Storage for pictures and files: a home for photos and documents that are too big for the database.
- A domain name: your own web address, about $10 to $20 a year.
- Email sending: sign-in codes and receipts that come from your app.
- Payments: a way to take money, inside the app and on your website. These take a small share of each sale.
- Address search: addresses that fill themselves in as someone types.
- Notifications: the messages your app sends to the phone's screen.
- Crash reports: a note when the app crashes on someone's phone, so you can fix it.
A card app needs three more: card data (names, sets and numbers), prices, and card pictures. They come from outside sources, each with its own terms, and some charge per use. Part 9 compares the options, and you pick what fits your app and your budget.
Money
Last checked October 27, 2026