Domains
Domains is where your app gets its own address: the domain people open it on, and — for one domain per app — the one its email comes from. Add a domain, publish the records it lists, and see each one found.
The walk
The room
Open Domains to see the domains your app runs on, what each one is for, and where it stands.
One domain
Open a domain to see whether it's proven yours, how many of its records were found, and what it's for.
Choose Remove to take a domain off your app; it asks first, and nothing is deleted at your DNS provider.
Records
Open Records for every DNS record the domain needs, each with its name, its value to copy, and whether it was found.
Add them where your domain's DNS is managed, then choose Check again: each one says found as soon as DNS answers.
Add a domain
Choose + Add domain and say where your app lives — a phone-only app has no web address to prove, and can still send email from your name.
Type the domain without www: the apex covers the www form, and Gemmein reads its records while you carry on.
Say whether it also sends your app's email. Receiving needs nothing from your DNS — replies already land in your Inbox.
One domain sends an app's email — this one already does, so a second domain here stays web-only, or Not for now.
What it refuses and why
These are the console's own words when a change can't be saved or a request can't go through.
Your app already sends from mail.petpix.app. One domain sends for an app — remove that one first to move it.
An app's email comes from one domain, so customers see one set of addresses and every reply reaches the same Inbox.
Where your app's email comes from, and its three sender words: Email.