Self-described "Māori boy from Gizzy" Mātai Rangi Smith was educated at Kaiti Primary School, Ilminster Intermediate and Gisborne's Lytton High School. When he began at Lytton, te reo classes "struck a certain chord with me and it just grew from there". While he won placings at a speech competition in Auckland, he was talent-spotted by TV producer Hinewehi Mohi. She offered Smith a job in 1996 as a researcher and reporter on Māori affairs show Marae

By 1998 Smith was directing and presenting the Sunday morning show on TV One: "Live was a buzz, no room for mistakes and if you did [make them], well then you had to learn how not to dwell on it and move on." 

Nine years followed as co-host of Pūkana, the first total Māori language children’s programme. Debuting on TV Four as Tūmeke, the show found its permanent name after moving to TV3 in its second year.  Pūkana identified te reo as its point of difference, and focused on reaching viewers from kura kaupapa Māori (Māori immersion schoolchildren). "Pūkana became that vehicle to provide them with content that reflects the world they were growing up in," says Smith. Inspired by the energy of mainstream shows like What Now?, the emphasis was on ‘street’ rather than formal marae-style language; hip hop and sky-diving clips showed kids that “there are terms for things like the popular skateboard move, fakey rock — takahuri teka." 

The show won Best Children’s Programme at the 1999 NZ Television Awards (under the title Tūmeke), and again in 2003 at the Qantas Media Awards, and scored the Kōrero Māori Best Māori Language Programme at the 2005 NZ Screen Awards. Starting in 2005, Smith would win best male Māori language presenter award for three consecutive years at the Māori Media Awards. He also did time as a producer on both Pūkana, and quiz show Ihumanea.

In 2007, during Te Wiki o Te Reo Māori / Māori Language Week, Smith hosted a slot teaching Good Morning presenters Brendon Pongia, Sarah Bradley and Steve Gray some simple words and phrases. His kaiako (instructor) role proved popular, and was expanded into a weekly segment. "The presenters were so into it and would have no qualms in getting it wrong or singing a waiata with me on the guitar ... a real blast!"

In 2016 Smith praised the breakfast show for being one of the only shows that had extended its willingness to give te reo "a go" — by making it a part of regular programming. "I was allowed to open the show with a Māori mihi or greeting and even throw to commercial breaks with lines like 'Kia mau tonu mai' (stay with us), then welcome viewers back with 'Nau mai, hoki mai'. It wasn’t even frowned upon or given a second thought."

Smith went on be a Good Morning presenter, emceeing a ‘live’ wedding at Avalon Studios, celebrating Sir Howard Morrison’s 73rd birthday in a three-hour special, and being hypnotised on air in 2012, alongside co-host Jeanette Thomas. The hypnotism episode went viral, after Peter Powers convinced him he'd won Lotto, and that he was interviewing Tom Cruise (actually Good Morning chef Laurent Loudeac). "I wasn’t acting, I can assure you!" 

Smith was one of the show's final presenters when its run came to an end in December 2015. While presenting Good Morning in 2010, Smith began hosting Māori Television’s Friday night talent show Homai Te Pakipaki. It became a cult hit for its Māori take on the talent show kaupapa, mixing, in Smith's words, the "diamonds" with "the rough". "That was the beauty of Homai Te Pakipaki: if you didn’t want your make-up done or your hair brushed, it was fine: you could still sing your way into the hearts of the viewers and hopefully get them voting for you that night." 

Smith reflected later that the show allowed him "to be a little more 'me' in terms of wit, and because I love to sing as well; so there was no more perfect show than this one for me to host." In 2012 Smith's mother was on hand to see him win Best Presenter in the Entertainment/Factual section of at the New Zealand TV Awards.

To date, Smith has interviewed subjects ranging from politicians to All Blacks, from Taika Waititi and Dame Kiri Te Kanawa, to his kuia Nina Buxton (for a 2016 Waka Huia documentary). He has also been a commentator on Māori media.

In 2013 Smith and his partner Alby Waititi (from reality show The GC) were featured as subjects in a Native Affairs report on Louisa Wall’s successful push to get the marriage equality bill through parliament. "We were stoked to have played a very small part in giving Louisa the tautoko she needed at the time."

Smith's efforts to champion te reo on screen have formed a thread throughout his career. From 2009 to 2012 he was the presenter of Kōrero Mai, an educational series that was pioneering in using a soap opera format to encourage youngsters to learn te reo. For Te Wiki o Te Reo Māori in 2014, Smith produced the song 'Aotearoa', motivated by New Zealand's last te reo number one (‘Poi E’) having been three decades before. Stan Walker was backed by singers Troy Kingi, Vince Harder and Ria Hall; the song got to number two in the charts.

Smith went on to become Australian correspondent for current affairs show Native Affairs.

Sources include
Mātai Smith
Yvonne Tahana, 'TV Presenter of the Year loses his job' - The NZ Herald, 23 January 2013
'Pūkana Premieres on Maori Television' (Press release) Scoop website. Loaded 24 January 2006. Accessed 31 August 2016
'Iconic Children's Show Pūkana Debuts Three New Presenters' (Press release) Scoop website. Loaded 5 March 2015. Accessed 31 August 2016
Unknown writer, 'Mātai Smith' (Interview) Wicked website. Accessed 31 August 2016