As a user of both Mac and PC computers, I had struggled for years to find a password manager that was truly mobile across platforms and locations. The best solution for me, so far, has been Roboform Online, which is a free account that works with their Roboform Pro software ($29.95). Roboform Online (and associated Javascript bookmarklet) not only works with PC, Mac, and browsers including Chrome, Opera, and Safari, but also with iPhones and Android Phones.