Tobii Dynavox (formerly DynaVox Mayer-Johnson) is a U.S.-based developer, manufacturer and distributor of speech generating devices headquartered in Pittsburgh, Pennsylvania. The company was formed in 1983 and has since become the leading provider of speech communication devices and symbol-adapted special education software used to assist individuals in overcoming speech, language and learning challenges. DynaVox Mayer-Johnson's stated mission is to enable children and adults to reach their educational potential and experience a greater quality of life by maximizing each person’s ability to communicate and learn. The company's best-known products include the Maestro and EyeMax System communication solutions, and the Boardmaker Software Family, a suite of tools that allow educational curriculum and activities to be adapted to meet a range of student learning, cognitive and physical needs.

Founded as Sentient Systems Technology, Inc. in 1983, the company’s first product was the EyeTyper. Created as a student project at Carnegie Mellon University to help a young woman with cerebral palsy to communicate, the EyeTyper allowed individuals spell messages with their eyes. These messages were then “spoken” by a computerized voice.

The EyeTyper made it possible for some people with cerebral palsy to communicate effectively. Killiany formed the company with CMU professor Mark Friedman and business partner Tilden Bennett. The patent for this technology was sold to the US Navy and all revenue went back into further development of communication applications that could be used by more people with significant speech disabilities. In 1991 the first DynaVox branded product was released. The DynaVox was the first speech-generating device to feature touchscreen technology.

The company changed its name to DynaVox Systems Inc. when was acquired by Sunrise Medical Inc. in 1998., before being spun out again several years later. In 2004 DynaVox acquired Enkidu Research Inc. and Mayer-Johnson. In 2009 DynaVox Mayer-Johnson acquired BlinkTwice, and incorporated that company's product, the Tango AAC device, into the DynaVox product line. DynaVox acquired Eye Response Technologies in January 2010.

The company floated on the stock market in 2010, although as of September 2011, its stock had fallen by 29.8% year in the last year In 2012, after continued falling stock prices, Dynavox was warned by Nasdaq that if shares continued to be valued below $1 the company would be dropped from the exchange. "The company intends to consider available options to resolve the noncompliance with the minimum bid price requirement," DynaVox said in a recent SEC filing. "No determination regarding the Company's response has been made at this time." In a separate and unrelated matter, DynaVox said in a separate SEC filing that JoAnn A. Reed would not seek re-election to the company's Board of Directors when her term expires on Dec. 5, 2012. On April 10, 2013, Dynavox announced that it received notification on April 5, 2013 that The NASDAQ Stock Market LLC ("NASDAQ") had determined to delist the Company's Class A common stock from the NASDAQ Global Select Market, effective with the open of business on April 16, 2013. As previously disclosed, on October 2, 2012, the Company received a notice from NASDAQ indicating it was not in compliance with NASDAQ's $1.00 minimum bid price requirement. The delisting is the result of the Company's failure to regain compliance with this requirement. The Company did not appeal the NASDAQ staff's determination. The Company has been advised by OTC Markets Group Inc. that its Class A common stock will be immediately eligible for trading on the OTCQB marketplace effective with the open of business on April 16, 2013. The Company's Class A common stock will continue to trade under the symbol DVOX.

As of April 2014, the company found itself grappling with restructuring its assets and debts estimated at between $10 million and $50 million. DynaVox Intermediate LLC, became the focus of a threatened collateral sale by JEC Capital Partners LLC and Fondren Management LP.

JEC and Fondren bought DynaVox's secured debt March 2014, the culmination of a process that saw the troubled Pittsburgh company searching for a deal or refinancing to bail it out of financial trouble.

April 8, 2014 DynaVox Systems, LLC ("DynaVox"), announced on their website clarifications regarding the Chapter 11 filings made by certain related entities and then on April 09th began giving away a free app to SLP's - “DynaVox Compass for Professionals gives SLPs free access to the DynaVox Compass app to use on their own iPad or Windows tablet, along with a comprehensive set of training and support tools, to help them better evaluate and serve their clients,”

On May 22, 2014, it was announced that competitor Tobii acquired DynaVox, and integrated them into Tobii's integrated Assisted Technology division. The company was renamed Tobii Dynavox LLC. The US division remains in Pittsburgh.

DynaVox devices assist individuals who are unable to communicate reliably with their own voices due to cognitive, language and physical impairments. According to the 2005 US disability census, cognitive illnesses alone affect over 16 million people over the age of 15, while 35 million American’s were described as having a severe disability.

The devices produced by DynaVox closely resemble touch screen tablet computers. DynaVox uses a Microsoft Windows-based configuration as a platform to run proprietary InterAACt communiciation software.

DynaVox devices, like almost all Speech generating device, use a hierarchical set of pages that contain different vocabulary for different contexts or situations. DynaVox's particular system of organising these pages is called 'InterAACT'.

Dynavox produce a range of speech generating devices, including the very small 'Xpress', and the 'Tango', which was designed particularly for children. Its newest device is called the Maestro, which, like the older V+ and VMax+ and M, provides options for multiple communication channels including cell phone, text messaging and e-mail. The larger Vmax is typically selected for those using wheelchairs (the device can be mounted) or for individuals with visual impairments. All Dynavox devices can be accessed in a variety of ways to compensate for limited physical abilities. The M is physically similar to the V+ and provides a limited number of prerecorded messages, and is often used by individuals with limited or no literacy skills.

DynaVox also produced the EyeMax, which is an accessory which allows someone with limited or no fine motor skills to use their eyes to control their device. Augie Nieto, founder of Life Fitness, member of DynaVox's board of directors, and the former "King of Fitness", was diagnosed with ALS, and has slowly lost movement in most of his body and his ability to speak. Nieto has been able to continue communicating with his family, friends, and the world using the EyeMax technology. The EyeMax Systems' camera tracks the person’s eye movements on the screen. The user makes a selection by blinking or pausing on the desired vocabulary. Nieto says, “I can type up to 20 words per minute with the DynaVox” using only his eyes.

On April 5, 2013, DynaVox received a notice from the NASDAQ that it will be delisted from the NASDAQ Global Select Market effective April 16, 2013. It has been eligible for trade in the OTC Markets Group marketplace since April 16, 2013. The delisting is the result of the company's failure to regain compliance with this requirement.

After the close of stock market trading on April 26, 2016, the security "DVOXQ" was delisted from OTC. The company went private.