|Headquarters||Cambridge, England, United Kingdom|
|Type of site||Answer Engine|
|Launched||7 November 2007|
Evi (formerly True Knowledge) is a technology company in Cambridge, England, founded by William Tunstall-Pedoe, which specialises in knowledge base and semantic search engine software. Its first product was an answer engine that aimed to directly answer questions posed in plain English text, which is accomplished using a database of discrete facts. The True Knowledge Answer engine was launched for private beta testing and development on 7 November 2007.
In January 2012 True Knowledge launched a major new product Evi (pronounced ee-vee), an artificial intelligence program which can be communicated with using natural language via an app on iPhone and Android.
The company changed its name from True Knowledge to Evi in June 2012.
Core technology premise 
The True Knowledge Answer Engine attempts to comprehend posed questions by disambiguating from all possible meanings of the words in the question to find the most likely meaning of the question being asked. It does this by drawing upon its database of knowledge of discrete facts. As these facts are stored in a form that the computer can understand, the answer engine attempts to produce an answer to what it comprehends to be the question by logically deducing from them. For example, if one were to type in “What is the birth date of George W. Bush?”, True Knowledge would reason from the facts “George W. Bush is a president”, “George W. Bush is a human being”, “A president is a subclass of human being”, “Date of creation is a more general form for birth date”, and “the 6th of July is the date of creation for George W. Bush”, to produce the simple answer, “the 6th of July”. True Knowledge differs from competitors like Freebase and DBpedia in that they offer natural language access. Unlike the others however, users who post information to True Knowledge granted the company a "non-exclusive, irrevocable, perpetual licence to use such information to operate this website and for any other purposes".
Knowledge accumulation and verification 
Evi gathers information for its database in two ways: importing it from "credible" external databases (which for them includes Wikipedia: Citation Required) and from user submission following a consistent format and detailed process for input. True Knowledge strives to monitor this user submitted knowledge in multiple ways. One method involves a system of checks and balances in some ways similar to Wikipedia's, allowing users to modify or “agree”/“disagree” with information presented by True Knowledge. The system itself also assesses submitted information due the fact that the information is submitted as discrete facts that computers can understand. The system is able to reject any facts that are semantically incompatible with other approved knowledge. On November 21, 2008, True Knowledge announced on its official blog that over 100,000 facts had been added by beta users and as of August 2010, the True Knowledge database overall contained 283,511,156 facts about 9,237,091 things.
On May 7, 2007, True Knowledge Ltd. announced it would be “actively seeking investments following several years of internally-funded development”. Then, on September 17, 2007, Octopus Ventures, a British venture capitalist firm, announced its investment of more than $1.2 million into True Knowledge, the first significant investment into the company, allowing it to further develop its website and achieve critical milestones towards bringing the True Knowledge Answer Engine to market. On July 30, 2008, True Knowledge announced it had raised another $4 million in a second round of funding from Octopus Ventures and other investors that would be used towards expanding its staff, developing new products, and moving towards a rollout within 12 months.
Evi is a cloud-based Artificial Intelligence (AI) which builds upon the core semantic search technology developed by the company and adds conversation, external APIs, location sensitivity and other features. Users can talk to Evi via an iPhone and Android app. Voice is supported. The company calls this "conversational search".
While initially only launched for mobile devices, it has been mentioned by Evi that the scope goes much further and in future she can be integrated into almost any other device, including cars, computers televisions, and more.
In May an update was released on both Android and iOS that introduced voice controls for phone, SMS, and email. This was announced as the first phase of phone control updates which will add further functionality and deeper integration with device features.
Data used by 
See also 
- MediaGuardian 100 2009 The Guardian (newspaper). 13th July 2009
- A billion facts mean Evi has the answers Cambridge News (newspaper). 19th February 2012
- New Virtual Helper Challenges Siri Technology Review (MIT). Rachel Metz. 27th January 2012
- Cambridge AI specialist seeks funding for latest exciting venture. 7 May 2007. True Knowledge. Retrieved 2 Dec. 2008
- Technology. True Knowledge. Retrieved 2 Dec. 2008
- True Knowledge launches open beta. 7 November 2007. TechCrunch. Retrieved 2 Dec. 2008
- Apple iPhone Siri, meet competitor Evi, from True Knowledge. Alternative to iPhone 4S. Global Post. Richard Orange. January 24th 2012
- Hands-On: Evi App Brings Siri-Like Smarts to iOS and Android January 24, 2012. Wired.
- Evi arrives in town to go toe-to-toe with Siri Jan 23 2012. Techcrunch
- Mike Butcher (14 June 2012). "Siri’s Nemesis Evi Relaunches, Recruits Berkowitz From Wolfram Alpha, Opens US Office". Retrieved 16 June 2012.
- "legal". Retrieved 2009-01-05.
- True Knowledge: The Natural Language Question Answering Wikipedia for Facts Semantic Focus. February 26th 2008.
- Bradley, Phil. True Knowledge - Questions Search Engine. 22 Sep. 2008. Phil Bradley's Weblog. Retrieved 2 Dec. 2008
- Franklin, Nick. Over 100,000 User Added Facts Have Gone In! 21 Nov. 2008. True Knowledge. Retrieved 2 Dec. 2008
- Stephen Adams (26 November 2010). "Computer identifies the most boring day in history". The Daily Telegraph. Retrieved 30 November 2010.
- "April 12, 1954 was most boring day in history". The Times of India. 26 November 2010. Retrieved 29 November 2010.
- Octopus Ventures invests over half a million pounds (>$1m) in the development of True Knowledge. 17 Sep. 2007 True Knowledge. Retrieved 2 Dec. 2008
- True Knowledge Reaches New Funding Milestone. 30 July 2008. True Knowledge. Retrieved 2 Dec. 2008
- True Knowledge API lies at the heart of real business model ZDNet. April 13, 2009.