I use it to generate new passwords for whatever signups/apps I need on mobile, also for logging into websites on mobile. The workflow for password managers in mobile safari works very well.
I don't enable FaceID/TouchID/PIN for 1Password, but I do have it enabled for my device.
Anyways, I use the Bitwarden app on my S8 (and previously HTC 10) and it works great. I tap a password field, Android asks me if I want to fill the password, I unlock my "vault" with my fingerprint, and tap the right account for that app. It's pretty easy.
LastPass and Bitwarden also can hook into accessibility features on Android 7, to enable most of the same features, but since it's not part of Android and baked in it doesn't work quite as well.
I used to use LastPass and frankly it's far behind 1Password in user experience, especially on Apple devices.
But the alternative seems to be staying logged in to LastPass which means it's just my four digit phone pin to get access to everything. I mean, I guess if someone takes my phone and bypasses my PIN then I've already lost basically everything. But at least I wouldn't also be signing them into my bank account. My phone doesn't have biometrics which I think would be my compromise if it had them.