On some iPhone 1Password says it can't verify the app.

Hi there inab

It sounds like 1Password isn't able to suggest your Login item when you autofill in that app. This will usually be because the "website" field in the Login doesn't match the app's "Associated Domain" – that is, the website address which is claimed by that app for autofill purposes. For example, the Facebook app claims facebook.com as its Associated Domain, so that items matching that address are suggested automatically.

Here's what to try:

1. Open the app in question.
2. Tap the Password field, then the "🔑 Passwords" button on the keyboard.
3. Check the "Suggestions For" header that appears in the autofill pop-up that appears.

If the "Suggestions For" header also includes a website address, that's the Associated Domain, and you should make sure that the "website" field of the Login matches this.

If the "Suggestions For" header just says “No suggestions" with no address, then the app developers haven't set an Associated Domain, and you'll have to search for it each time, because neither iOS nor 1Password will know what to suggest. That would be something that only the app developers can fix, as it's part of how the app is written. In that case, I'd advise contacting them through the "App Support" link in their App Store listing to give them your feedback.

Because of how autofilling works on iOS, there's no way to identify which app is which (for autofill purposes, at least) using any other method, so you can only approve autofilling into an unrecognised app once at a time, to make sure that item can't be blindly autofilled into any app.

Let me know if you have any questions. :)

— Grey