I think I am correct in saying that all of the suggested apps have this in common:
There is a master password (call it what you will) that you, and only you know. Lose it or forget it and no one anywhere can help you because it is not logged on the Internet.
So it comes done to personal choice, expense (free or pay for) and trust. Trust, in large part, being the safety record of each app. And that correlates with the length of time that app has been around, how responsive it is to feedback from users and how quickly it adjusts to new OS and iOS.
I have my personal favourite, but make no direct recommendation. Instead I invite you to research these values for yourself and form your own conclusions.
Ian