Years ago, mobile devices fell under the category of cell phone or mobile phones. These served the purpose of sending voice signals to and from these mobile devices.
However, with the shift in technology, mobile devices now fall under the categories of smartphones, PDAs, or mobile phones.
Smartphones are a hybrid mix of mobile phones and PDAs.
PDAs are like a small computer which allows the user to combine telephone/fax, fax, internet and networking features. Traditionally, the PDA has not had telephone but this has all changed these days.
The smartphone combines the PDA with the mobile phone. With more emphasis on the mobile phone part, the user can store information, use the Internet and send data and voice-centric information.
But it can do alot more with third-party software - which usually costs less than $20.
Smartphones come built with standard functionality which allow the user to send email, use a diary/calendar, camera and infrared/bluetooth applications.
However, third-party software can also increase the functionality of the smartphone, for example by including global positioning software, or time management software.
Most software is bought over the internet for a low cost, and the major supplier for smartphone software is a firm called Handango.