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02 — What's an app?

Part 2 of 7 · ← Where to start · Index · Next → An app in insurance

An App in ChatGPT is a small program you build that lives inside the chat. OpenAI's official name for it is an App (built with the "Apps SDK"). Some people also call it an agent.

When a user types something your app handles, ChatGPT opens a panel right there in the conversation — your UI, your data, your shape.

Three real examples

  • Figma — "turn this sketch into a diagram" → Figma panel with the diagram.
  • Zillow — "3-bedroom in Austin under $500k" → map + listings inside the chat.
  • Spotify — "make me a focus playlist" → player inside the chat.

Who does what?

Think restaurant:

  • User = customer. Asks in plain words.
  • ChatGPT = waiter. Understands the order, routes it to the right kitchen.
  • Your app = kitchen. Two parts:
  • A brain — a small server online. Does the work.
  • A face — a visible panel. Shows buttons and data.

You build both parts of the kitchen. ChatGPT handles everything else.