Your marketplace inside ChatGPT: how official apps work, and why early matters
A ChatGPT app lets a business answer users inside ChatGPT with its own live data. For a marketplace, that means a user who asks ChatGPT for a used estate car or a two-bedroom flat can see real listings from that marketplace, under its name, and click through to contact the seller. Apps are built on MCP and published in ChatGPT's app directory.
How do apps in ChatGPT work?
OpenAI introduced apps in ChatGPT in October 2025, together with an Apps SDK built on the open MCP standard. Users can call an app by name, or ChatGPT can suggest one when it fits the conversation. OpenAI's own example: someone discussing buying a home is offered a property portal's app and browses matching listings on a map inside ChatGPT.
An app turns a mention into a visit. Without an app, ChatGPT may describe a type of car in general terms. With an app, it can show the specific listings a marketplace has today, with prices, photos and a link back to the listing.
How big is the audience?
OpenAI reported in February 2026 that ChatGPT has 900 million weekly users. Shopping is a real share of that use: a working paper by OpenAI's economic research team, reported by Modern Retail, estimated that around 2% of ChatGPT queries are shopping-related, roughly 50 million a day.
What does publishing an app take?
OpenAI reviews every submission. According to Moburst's guide to the directory, a listing needs an app name and icon, descriptions, screenshots, a verified website, a configured MCP server and test cases showing the app works on web and mobile.
- An MCP server connected to your live listings and search.
- A conversational layer that understands requests in natural language.
- Brand assets, descriptions and a privacy policy.
- Testing across real user questions before submission.
Why does timing matter?
Directories reward relevance, and the first credible app in a category has room to become the one users and the assistant return to. A marketplace that waits risks having its category answered by general knowledge, or by someone else's listings.
The app is published under the marketplace's name. Users see your brand, your listings and your link. The lead lands on your site, where the seller relationship already lives.
Does an app replace the website?
No. The app is an entrance, not a destination. Contacts, payments and the relationship with the seller stay on the marketplace. The app brings users who were already asking about what you sell.
Where Mira fits
Mira builds and hosts your MCP, connected to your live listings, and packages it for ChatGPT: we build the app with OpenAI's Apps SDK and prepare the directory submission. The same MCP works in Claude and other assistants. It runs on the same engine as Mira on your site (widget), and you publish under your own name. See how Mira works for marketplaces.
Frequently asked questions
Is the app available in Europe?
Apps launched first outside the EU and have been expanding. Availability by country is checked at the start of each project.
Who owns the app?
The marketplace. It is published under your name, and you decide what it shows.
Do we need our own engineers?
Your team joins a technical call and approves the setup. Mira builds and hosts the connection.