Every word, in plain words.

Every technical word the course uses, in the order you'd look them up. Each one is also explained the first time it appears in a lesson, in a box marked 📖.

A

A record. A DNS record that points a name at a server's address (four numbers with dots).

A/B test. Comparing version A with version B of something, changing one thing at a time.

Account. A person's sign-in that keeps their things separate and brings them back on a new phone.

Alias. An extra email address that delivers into an inbox you already have.

Analytics. A service that counts what visitors do on your site or app. It still counts as collecting data.

API key. A long password that lets one program use another, like your site using Resend to send email. Anyone who has it can act as you, so it goes only where the lesson says, never in a chat or a screenshot.

App Privacy. Apple's questionnaire about what data your app collects, shown on your store page as a privacy label.

App Review. Apple's team that tries every app before it appears in the App Store. A rejection is normal and fixable.

App Store. Apple's shop for iPhone apps. Every app is reviewed before it appears.

App Store Connect. Apple's website for managing your app after it exists: store page, testers, prices and review messages.

Apple Developer Program. Apple's paid membership ($99 a year) for putting apps on other people's iPhones.

Archive. A packaged copy of your app, ready to send to Apple.

Authentication. The part of a backend that handles sign up, log in and passwords.

B

Backend. The part of an app that lives on a server, not the phone: accounts, saved data, payments. In this course, Supabase.

Branch. A separate copy of your project where changes happen without touching the live site. It gets its own preview link.

Brand guidelines. A short document saying how your business looks and sounds: colors, fonts, voice, and what it never does.

Browser pane. A small web browser built into the Code tab, next to the chat.

Bucket. A folder in Supabase Storage for files such as photos. Public or private.

Build. One packaged, installable copy of your app. "Build failed" means something stopped it being made.

Build number. Xcode or Expo's counter for every upload. The version number is what people see; the build number just counts.

Bundle ID. Your app's permanent ID in Apple's system, written like a backwards web address (com.yourname.app). It can never change.

C

Certificate. Apple's proof that a build came from you. Expo or Xcode makes and stores it.

Claude Code. The part of Claude that writes code and saves it as files on your Mac.

Claude Design. The part of Claude that draws screens. It makes a picture, not code.

CLAUDE.md. A plain text note in your project folder that Claude Code reads at the start of every session.

CNAME record. A DNS record that says one name is an alias for another name.

Code tab. The tab in the Claude desktop app's sidebar where Claude Code lives.

Code signing. A certificate plus a provisioning profile proving an app came from you. Expo manages both.

Commit. Git's word for one save point: a snapshot of every file plus a short note. "Push" sends it to GitHub.

Connected account. The Stripe account belonging to one seller or sitter, created through your marketplace.

Conversion rate. The share of people who arrived and then did your one job.

Cron job. A task that runs on a schedule by itself.

Customer portal. A page Stripe hosts where a customer manages their own subscription.

D

Dashboard. A service's website where you manage your account and make or delete keys.

Dark mode. The iPhone setting that turns screens dark. Apps need colors for both looks.

Database. Where an app keeps everyone's things, in tables like spreadsheets, on Supabase's computers.

Deep link. A link that opens a screen inside an app instead of a web page.

Deploy. To put a version of your site onto the internet. Vercel does it automatically from GitHub.

Design system. Your brand guidelines made usable: exact colors, type sizes, spacing and button styles every screen is built from.

Developer Mode. An iPhone setting that lets a Mac install apps on it directly.

Development build. Your own copy of Expo Go built for your app. It can make purchases, but still reloads code from your Mac.

DKIM. A signature on your outgoing email that inboxes check against a DNS record.

DMARC. A TXT record on _dmarc saying what inboxes should do with email that fails the checks.

DNS. The internet's contacts list. It turns a domain name into the address of the computer that answers.

DNS record. One line in your domain's settings at your registrar, saying where something should go.

Domain. Your address on the internet, like yourname.com, rented by the year.

D-U-N-S number. A free nine-digit business ID from Dun & Bradstreet. Apple uses it to confirm a company exists.

E

EAS. Expo Application Services: Expo's build servers, which produce the app file Apple accepts.

Edge Function. A small piece of code that runs on Supabase's servers, for anything that needs a secret key.

EIN. A nine-digit tax number for a business, like a Social Security number for your company. Free from irs.gov.

Embed code. A block of code a service gives you to show its form or calendar on your page.

Empty state. What a screen shows before there's anything on it.

Entitlement. RevenueCat's word for what a subscriber has unlocked, such as "pro".

Environment variable. A named setting your project reads when it starts (NAME=value). It lives in a private .env.local file on your Mac and in Vercel's settings when live, so keys never sit in code.

Error message. The text a program shows when something goes wrong. It's written for Claude, so paste it whole.

Error tracking. A service that catches every crash on the live site and reports it to you.

Event. One thing a person did, recorded with a time, such as "signed up" or a page view.

Expo. Free tools that turn Claude's code into an iPhone and Android app without Xcode. Expo Go is the phone app that previews it.

Export. Saving a copy of your design as ordinary files on your Mac.

External testers. People outside your developer account who test your app through TestFlight.

F

Funnel. The steps toward paying, and how many people drop off at each one.

G

Git. A tool that keeps a saved copy of every working version of your project, like version history for a folder.

GitHub. A website that stores a copy of your project's files and every version: an off-site backup with history.

Guideline 1.2. Apple's rule for apps with user content: you need filtering, reporting, blocking and a way to contact you.

H

Host. The company whose computers serve your site to visitors. In this course, Vercel.

HTML file. A web page saved as a single text file ending in .html. Any browser opens it.

HTTPS. The padlock. An encrypted connection between the visitor and your site, free from Vercel.

I

In-app purchase. Buying something inside an app through Apple. Apple takes the payment, keeps its cut and pays you.

L

Launch screen. What shows while an app starts.

Live mode. Stripe's name for real payments: a separate copy of your account with its own keys, products and customers.

LLC. A limited liability company. A simple company registered with your state that's a separate "person" with its own name and bank account.

localhost. An address that means "this computer". Only your own Mac can see pages there, like localhost:3000.

M

Marketplace. An app where two groups trade with each other and the app sits in the middle, taking a small fee.

Migration. A saved, dated set of changes to the database's structure, replayable on the live database.

MVP. Minimum viable product: the smallest version people would pay for.

MX record. A DNS record saying which mail servers receive email for your domain.

N

Nameserver. The computer that holds your DNS records. Don't change it unless a lesson says to.

Next.js. The kit of ready-made parts Claude builds your website with: pages, addresses and publishing.

Node. A free program that runs website and app code on your Mac. Installed once, used by Claude.

O

Offering. RevenueCat's word for the set of plans your upgrade screen shows.

P

Password manager. An app that stores passwords and secrets behind one master password.

Paywall. The screen shown when someone taps a paid feature, with what they get and the price.

Payout. Money leaving Stripe for someone's bank account.

Permission. The Allow / Don't Allow pop-up on an iPhone, with your sentence under it.

Phased release. An App Store option that rolls an update out over seven days. You can pause it.

PNG. A picture file type. Your app icon is one 1024-pixel square PNG with no transparency.

Points. The unit iPhone screens are measured in. 44 points is a fingertip.

Price ID. Stripe's name for one specific price (price_…).

Privacy label. The App Privacy box on your store page, like a nutrition label for data.

Product ID. The short, permanent code name of one thing for sale. Spelled identically everywhere.

Project (Claude). A folder inside Claude, not on your Mac, that groups chats about one idea with shared background notes.

Project folder. An ordinary folder on your Mac holding everything for one app or site.

Propagation. Old cached DNS answers expiring while a change spreads. This is why DNS changes take time.

Property. Google's word for one website you've proved you own.

Public key. A key that's safe to put in your app, where anyone could see it. It only has harmless powers. Supabase calls it the publishable key.

Push. To send your latest saved version from your Mac up to GitHub. Vercel watches for pushes and publishes each one.

Push notification. A lock-screen message that arrives even when the app is closed.

R

Realtime. Supabase pushing a change to every phone the moment it happens, such as a new chat message.

Registered agent. A person or company with a street address in your state who receives legal mail for your LLC.

Registrar. The company you buy and renew a domain with.

Repository. One project's folder with its whole history of saved versions, kept on GitHub. Short form: repo.

Resolution Center. The message thread between you and Apple's reviewer in App Store Connect.

Restore Purchases. A button Apple requires, which re-unlocks a purchase on a new phone.

RevenueCat. A service that sits between your app and Apple's payments and keeps track of who has paid.

Role. A label on an account saying what it may do, such as user or admin.

Route. The address of a page, like /pricing.

Row Level Security (RLS). Rules in the database deciding, row by row, who can read or change what.

S

Sample mode. The app runs on made-up data stored inside the app itself. Nothing leaves the phone yet.

Sandbox. Apple's practice version of payments. Purchases go through every screen but charge no real money. Stripe's test mode is the same idea.

Scheduled job. Code that runs on its own at a set time.

Secret key. A master password for a service. It could charge customers or read your whole database, so it goes in .env.local and Vercel only, never in the app, a chat or a screenshot.

Server. A computer somewhere else that your app talks to.

Service role key. Supabase's secret key, which ignores Row Level Security.

Session. One conversation with Claude Code about one folder. It starts fresh each time.

Signing secret. A second Stripe secret (whsec_…) proving a webhook message really came from Stripe.

Simulator. A pretend iPhone in a window on your Mac.

Sitemap. A plain list of every page on your site, written for Google, at /sitemap.xml.

SMTP. The standard way one computer hands an email to another to deliver.

Sole proprietor. What you are automatically when you sell anything without forming a company.

SPF. A TXT record listing who may send email as your domain.

SQL. The language databases understand. Claude writes it, you paste it.

StoreKit. Apple's in-app selling system. A StoreKit configuration file is a practice price list.

Stripe. The company most apps and sites use to take card payments. Stripe Connect is the part built for marketplaces: it takes payment, keeps your cut and pays the seller.

Stripe CLI. A Terminal tool that relays Stripe's messages to a site running only on your Mac.

Subdomain. A name in front of your domain, like updates.yourdomain.com, treated separately.

Subscription. A payment that renews automatically until cancelled. Apple handles it end to end for apps.

Subscription group. Apple's grouping of different ways to pay for the same thing, such as monthly and yearly.

Supabase project. One app's backend: database, sign-in and keys under one name.

Support URL. The public help page address Apple requires for every app.

T

Table. One kind of stored information, laid out like a spreadsheet.

Tabs. The row of icons along the bottom of a phone app, one per main screen.

Team. Apple's word for who an app belongs to. A Personal Team is free and just you.

Terminal. A Mac app where you type a command and press Return instead of clicking buttons.

Test mode. Stripe's practice copy, where cards are fake and no money moves. The card 4242 4242 4242 4242 always works there.

TestFlight. Apple's free app for trying apps before they're in the App Store. Builds last 90 days.

TTL. How many seconds other computers may keep a copy of a DNS record. It's why changes take a while to show.

Two-factor sign-in. A second check after your password, usually a six-digit code from an app.

TXT record. A DNS record holding a line of text that a service reads to prove you own the domain or to authorise senders.

U

Usage limit. How much Claude you can use before it asks you to wait. It refills on its own.

V

Version number. The number people see in the App Store, like 1.2.

W

Webhook. A message one service sends another when something happens: Stripe telling your site "this person paid".

WHOIS privacy. Replacing your details in a domain's public owner record with the registrar's.

X

Xcode. Apple's free Mac app that turns Claude's code into an iPhone app and sends it to Apple.