I only know one password: my master password for LastPass. There's absolutely no possible way I could ever memorize all the passwords I have across various sites on the internet (well, maybe I could, but I don't want to). Simply put, password managers are a godsend.
If you're not into LastPass for whatever reason (or just looking for something new), it may be time to check out PasswordBox. It's basically on par with LP when it comes to price ($12/ year) and having you covered across multiple devices (Android app and Chrome extension), but as of the most recent update to the Android app, it also boasts a feature that LastPass can't hold a candle to: one-tap logins. It's killer.
It really works like that too (for the most part, anyway) – once everything is set up, open an app and let PWB do the rest. Not all apps are supported right now, but they claim roughly 80 percent of the 1000 top apps are already covered. That's a damn good start.
Of course, LastPass has its dedicated keyboard that can auto-fill usernames and passwords as well, but this method is far more elegant. It's literally one tap.
While the premium version of PasswordBox is $12/ year, there's also a free version that allows for storage of 25 passwords if you want to check it out before ponying up the cash. You'll find it at the widget below.