A cellular phone that can connect to the Internet for tasks like Web browsing and sending and receiving e-mail. They typically include a personal digital assistant.
A mobile phone with minibrowser internet access and advanced PDA capabilities (calendar, contact manager, to-do list etc).
a smartphone is the combination of mobile phone and handheld computer that has more features than other mobile phones. Smart phones allow users to converse as well as perform tasks, such as accessing the Internet, text messaging, and data services.