AutoFill login forms on iOS with Buttercup for Mobile

3 min readJan 18, 2019

Apple’s iOS version 12 came out with a fantastic new feature, allowing for login forms to be auto-filled with a user’s credentials that are stored in their favourite password manager. When the on-screen keyboard appears, password choices are presented at the top of the keyboard for easy access.

What this essentially means is fluid, efficient access to all of your login details without the need for in-app browsers that run complex scripts to perform the autofill for you. These are no longer needed on iOS and means users can simply stay in Safari without being relegated to these custom browsers. The new feature brings your passwords straight to you without the need to explicitly store your details on your phone or within iCloud.

There’s also the option to tap the Key icon instead, which brings up a menu with a few other choices, such as choosing another from the current password manager or by picking one from iCloud:

If you choose to find another from Buttercup you can search through your vaults for another credential:

Tapping the item above the keyboard or the search result in the screen above will trigger the filling of the login form with the details contained within the Buttercup entry.

This new functionality comes as a result of adding an extension to the Buttercup mobile app, which integrates with the iOS autofill system. To enable Buttercup’s autofill functionality, you must navigate to Settings > Passwords & Accounts > AutoFill Passwords and enable the setting.

You’ll notice, when enabling autofill, that you’ll be able to choose the password manager that can be used with autofill — but only one at a time:

Password managers are just secure databases, buttoned-down lists of information, they’re not executing code that can interfere with each other. Yet Apple has set a limitation: only one password manager at a time can be trusted with AutoFill. — AppleInsider

This may not be an issue if you’re only using one, but it’s an interesting decision on Apple’s part to impose such a limitation.

Once you’ve enabled Buttercup in this list, your credentials will become available when you interact with login forms in Safari. If you haven’t unlocked your vaults in Buttercup since upgrading to version 1.8.0, your credentials will not yet be available in the quick access menu above the keyboard. After you’ve unlocked your vault (either via the app or via the keyboard) your credentials will sync via the secure keychain so that they’re available in the future.

It goes without saying how useful this feature will be — having speedy access to your logins is one of the most important factors in designing password management utilities. It makes them appropriate for everyone to use as there’s little to no hurdle in using them on a daily basis.

A lot of effort was put into this feature, from our community, to get it where it is today — here’s a quick shout-out to se1exin who pushed this over the line!

Lastly — a quick thanks to all those who’ve donated on OpenCollective and to all our users, especially those on Twitter — your support is invaluable.




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