The trend at the time, however, that manufacturers competed on in both mobile phones and PDAs was to make devices smaller and slimmer.
The bulk of these smartphones combined with their high cost and expensive data plans, plus other drawbacks such as expansion limitations and decreased battery life compared to separate standalone devices, generally limited their popularity to "early adopters" and business users who needed portable connectivity.
In the mid-late 1990s, many people who had mobile phones carried a separate dedicated PDA device, running early versions of operating systems such as Palm OS, Newton OS, Symbian or Windows CE/Pocket PC.
These operating systems would later evolve into early mobile operating systems.
The two components were attached by a hinge in what became known as a clamshell design, with the display above and a physical QWERTY keyboard below.
The PDA provided e-mail; calendar, address book, calculator and notebook applications; text-based Web browsing; and could send and receive faxes.
It had a 640×200 resolution CGA compatible four-shade gray-scale LCD screen and could be used to place and receive calls, and to create and receive text messages, emails and faxes.When closed, the device could be used as a digital cellular telephone.In June 1999 Qualcomm released the "pd Q Smartphone", a CDMA digital PCS smartphone with an integrated Palm PDA and Internet connectivity.They are able to run a variety of software components, known as “apps”. event calendar, camera, web browser) come pre-installed with the system, while others are available for download from places like the Google Play Store or Apple App Store.Apps can receive bug fixes and gain additional functionality through software updates; similarly, operating systems are able to update.