Building your app
Custom domain
A custom domain is a web address you own, such as yourname.com, that opens your app instead of the default address your builder gave it.
Also called custom URL, branded domain
You buy the address from a domain registrar, a company that sells web addresses. Your host gives you DNS (domain name system) records, short lines of settings, to paste at the registrar. Changes can take a while to spread, so a domain that fails at first is often just waiting.
When this shows up
Example, not a real founder: you buy an address for your app and type it into your builder. The builder keeps showing a warning. The records were never added at the registrar, so the address still points nowhere.
What to do next
Copy the exact records your host shows into your registrar's DNS settings and save them. Check again later the same day before you change anything else.
Go deeper
My app works on my laptop but not for my friends. Why?
One set of tools you can build your app with and run on your own, one for each layer, each with a reason.
Read the guide