I am at the moment also trying out password managers and searching for the best one. Lastpass so far has the best features, great password generation. But on Android it lacks a good and decent integration in finding and selecting the correct password for an app. Seriously bad. 1Password is better in this regard, but you can not swipe the 1password "click here to fill out with 1password" away. So also definetly a deal…
I don't know about mobile (especially Android), but at least on Google's authentication page, even though it only visually presents the username field, the password field is already there and is filled out by 1Password.