Editing Personal digital assistant (section)

===Touchscreen===
[[File:Palm-IMG 7024.jpg|thumb|PalmPilot organiser on display at the [[Musée Bolo]], [[École Polytechnique Fédérale de Lausanne|EPFL]], [[Lausanne]]]]
Many of the original PDAs, such as the [[Apple Newton]] and [[Palm Pilot]], featured a [[touchscreen]] for user interaction, having only a few buttons—usually reserved for shortcuts to often-used programs. Some touchscreen PDAs, including [[Windows Mobile]] devices, had a detachable [[Stylus (computing)|stylus]] to facilitate making selections.<ref name="lenovo"/> The user interacts with the device by tapping the screen to select buttons or issue commands, or by dragging a finger (or the stylus) on the screen to make selections or scroll.<ref name="lenovo"/>

Typical methods of entering text on touchscreen PDAs include:

* A [[virtual keyboard]], where a keyboard is shown on the touchscreen. Text is entered by tapping the on-screen keyboard with a finger or stylus.
* An external [[keyboard (computing)|keyboard]] connected via [[USB]], [[Infrared port]], or Bluetooth. Some users may choose a [[chorded keyboard]] for one-handed use.
* [[Handwriting recognition]], where letters or words are written on the touchscreen, often with a stylus, and the PDA converts the input to text. Recognition and computation of handwritten horizontal and vertical formulas, such as "1 + 2 =", may also be a feature.
* Stroke recognition allows the user to make a predefined set of strokes on the touchscreen, sometimes in a special input area, representing the various characters to be input. The strokes are often simplified character shapes, making them easier for the device to recognize. One widely known stroke recognition system is Palm's [[Graffiti (Palm OS)|Graffiti]].

Despite research and development projects, end-users experienced mixed results with handwriting recognition systems. Some found it frustrating and inaccurate, while others were satisfied with the quality of the recognition.<ref>{{cite magazine |url=https://www.wired.com/gadgets/mac/commentary/cultofmac/2002/08/54580 |title=Apple's Newton Just Won't Drop |last=Kahney |first=Leander |date=29 August 2002 |magazine=Wired |publisher=Condé Nast Publications |access-date=21 August 2010 |url-status=dead |archive-url=https://web.archive.org/web/20100902084536/http://www.wired.com/gadgets/mac/commentary/cultofmac/2002/08/54580 |archive-date=2 September 2010 }}
* {{cite web|archive-url=https://web.archive.org/web/20080416113926/http://www.smalldog.com/newsarchive/kibbles_display.php?id=29|archive-date=16 April 2008|title=Kibbles&Bytes #29: Don's Review of the Newton Message Pad 2000|publisher=Small Dog Electronics|last=Mayer|first=Don|date=1 July 1997|access-date=18 February 2011|url=http://www.smalldog.com/newsarchive/kibbles_display.php?id=29}}
* {{cite web|url=http://www.h-net.org/~mac/mp2000.html|title=The Postgraduate Newton: a month in academia with Apple's new handheld computer|date=May 1997|first=Geoffrey|last=Klingsporn|publisher=The History and Macintosh Society|access-date=21 August 2010|at=note-taking}}
* {{cite web|url=http://perlnet.umephy.maine.edu/bio/wittmann/pooter/newtuse/hwr.html|title=What's Right With The Newton: Part I: Handwriting recognition|first=Michael C.|last=Wittmann|access-date=21 August 2010|url-status=dead|archive-url=https://archive.today/20060908164609/http://perlnet.umephy.maine.edu/bio/wittmann/pooter/newtuse/hwr.html|archive-date=8 September 2006}}</ref>

Touchscreen PDAs intended for business use, such as the [[BlackBerry]] and [[Palm Treo]], usually also offer full keyboards and [[scroll wheel]]s or thumbwheels to facilitate data entry and navigation. Multiple touchscreen PDAs support some form of external keyboard as well. Specialized folding keyboards, which offer a full-sized keyboard but collapse into a compact size for transport, were made available for multiple models. External keyboards may attach to the PDA directly, using a cable, or may use wireless technology such as infrared or Bluetooth to connect to the PDA. Newer PDAs, such as the [[HTC HD2]], [[Palm Pre]], [[Palm Pre Plus|Pre Plus]], [[Palm Pixi|Pixi]], and [[Palm Pixi Plus|Pixi Plus]], as well as devices running the [[Android (operating system)|Android]] operating system, include more advanced forms of touchscreen that can register multiple touches simultaneously. These "[[multi-touch]]" displays allow for more sophisticated interfaces using various gestures entered with one or more fingers.