Digital identities represent who we are when engaging in online activities and transactions. The rapid growth in the number of online services leads to in an increasing number of different identities that each user needs to manage. As a result, many people feel overloaded with identities and suffer from password fatigue. This is a serious problem and makes people unable properly control and protect their digital identities against identity theft. This paper discusses the usability and privacy in online identity management solutions, and proposed a general approach for making users better able to control and manage their digital identities, as well as for creating more secure identity management solutions. More specifically, we propose a user-centric approach based on hardware and software technology on the user-side with the aim of assisting users when accessing online services.