Nancy Schilling,
iCloud Mail, Gmail, and Yahoo Mail all use IMAP standards. With IMAP, your emails are stored on the server. When you make a change on one device, it pushes that change to the server, and then the server pushes that change to all of your other devices automatically. For example, if you delete mail in one place it should automatically delete everywhere else, like what you're used to seeing.
As long as the accounts are set up correctly on your devices, the changes should be pushed to all of your other devices. That's why it's important to narrow the issue down and identify exactly where the issue lies. The issue could be settings, server, or account related.
So to get you headed in the right direction, we'll need some very specific answers.
- Does this happen with emails from all of your accounts or one account in particular?
- Does this only happen if your delete the email on a particular device, or does it happen on all device you delete emails on?
- If you sign in to iCloud, Gmail, or Yahoo in a web browser and no the Mail app, then delete an email, does that get pushed to your devices?
We ask those questions for the following reasons. If this is only happening with one account, it points to an issue with the account and not your devices. If this is happening with all of your accounts it means it may be an issue with the Mail app, Settings on your devices, or the update, but it would likely be a settings issue since there doesn't appear to be a widespread app or update related issue right now. If the changes are being pushed to your devices from the website, it might be an incoming or outgoing server setting. Know those answers will help us better understand where the issue is stemming from.
Alternatively, you can remove those accounts from all of your devices and then set them up again. That might be the ultimate course of action anyway depending don't the root cause of the issue. Removing the accounts and adding them again ensures that the server settings are correct and resets fetch settings on your iPhone. Since the accounts are IMAP, removing the accounts shouldn't cause any data loss. That said, if you things like photos, contacts, notes, or other content from those accounts on your iPhone, you may need to redownload them after signing back in.
To remove an account go to Settings > Mail > Accounts > [account name] > Delete Account.
To add an account, follow the steps here: Add an email account to your iPhone, iPad, or iPod touch
We hope to hear back from you soon.