How to set up an email signature on your phone

Why the phone signature is different

Desktop clients store the signature on the computer (classic Outlook, Apple Mail) or with the account (new Outlook, Gmail on the web). Mobile apps ignore both and keep a third copy on the phone. That is why a new starter can have a perfect signature from their laptop and Sent from my iPhone from the train.

The table below is the short version; the sections after it have the steps.

Outlook app on iPhone and Android

1. Tap your profile picture (top left), then the gear icon for Settings.
2. Scroll to Signature.
3. Turn on Per account signature if you have more than one mailbox and want different ones.
4. Type the signature. Bold, italic and links are supported; images are not.

Outlook mobile does not pick up the signature from new Outlook or Outlook on the web, even for the same account. If your organisation uses UnifySig or another server-side tool, delete the mobile signature entirely so it is not added twice.

Gmail app on iPhone and Android

1. Tap the menu (three lines), scroll to the bottom and tap Settings.
2. Tap the account.
3. Tap Mobile signature (Android) or Signature settings (iPhone) and type the text.

The mobile signature is plain text and separate from the web one. If it is empty, the Gmail app on Android uses the web signature as a fallback for that account; on iPhone it does not. Google Workspace admins can push a signature to every account with the Gmail API, which is what UnifySig does, and that signature is honoured by the app.

Mail on iPhone and iPad

1. Open Settings → Apps → Mail.
2. Tap Signature, then Per Account if needed.
3. Type the text. Links and phone numbers are made tappable automatically.

Mail on the Mac can take a full HTML signature; the steps are in the Apple Mail guide. Nothing set there reaches the phone.

Samsung Email

1. Open the app, tap the menu, then the gear icon.
2. Tap the account, then Signature.
3. Turn the signature on and type the text.

Samsung Email supports plain text only. For Exchange accounts it does not read the mailbox's server-side signature setting, so the same advice applies: leave it empty if the signature is applied centrally.

Getting the same signature on every device

There are two honest answers.

Keep it short. If you manage your own signature, put name, title, company and phone in each app as plain text and accept that the logo only shows from the desktop. It is consistent enough, and it never breaks.

Apply it on the server. For an organisation, the only way to get the full signature from phones is to stop relying on the phone. UnifySig adds the signature after the message leaves Microsoft 365 or Google Workspace, so the Outlook app, the Gmail app, Mail on iPhone and a shared mailbox all produce the same result, and staff never set one up. Delete the mobile signatures once it is on, or they stack.