He studied mathematics at the University of Iceland, but quit after two years to get involved with the digital fabrication movement.
He is known for his work relating to direct democracy, transparency, privacy, and other subjects. At age one his family moved to England. At age 9, the family returned to Iceland, settling in Vestmannaeyjar, a town and archipelago off the south coast.
Smári got involved in the digital fabrication movement in 2007, and was involved in the creation of the first Icelandic fab lab in Vestmannaeyjar.
He has worked with Fab Labs elsewhere, including Jalalabad, Afghanistan. The same year, Smári proposed the Shadow Parliament Project, a project intending to "crowdsource democracy".
In an essay outlining the project, he described what is now known as Liquid Democracy. The project launched Skuggaþing (Icelandic for "shadow parliament") in early 2010.
In 2012 he started the wasa2il software project in order to address shortcomings with existing implementations of Liquid Democracy.
In 2008 he co-founded of the Icelandic Digital Freedom Society (FSFÍ), a free software, privacy and digital rights organization in Iceland. In 2009 he organized the Icelandic Modern Media Initiative along with various other media freedom and free speech activists, including Birgitta Jónsdóttir, Julian Assange and Rop Gonggrijp. In 2011 the International Modern Media Institute (IMMI) was formed around the initiative, with Smári serving as executive director
In 2012, he co-founded the Icelandic Pirate Party, along with Birgitta Jónsdóttir, Helgi Hrafn Gunnarsson, and various others
In the summer of 2013, Smári co-founded the free software project Mailpile along with Bjarni Rúnar Einarsson and Brennan Novak. The team successfully crowdfunded $163,192.
Smári"s role in the company is privacy and security. In 2014, Smári joined the editorial board of Scottish pro-independence newspaper Bella Caledonia.
Public speaking and activism Smári has spoken at numerous conferences, such as Oekonux, FSCONS, Internet at Liberty and Social Help and Rehabilitation Effort, as well as having lectured at various universities and summer schools.
Common themes include direct or electronic democracy, press freedoms, a critique of industrialization as a centralizing force, and the culture of the Internet. More recently he has spoken about privacy in the context of state surveillance. In 2012, WikiLeaks has alleged that Smári was approached by agents of the Federal Bureau of Investigation in Washington, District of Columbia
Smári has made appearances in We Steal Secrets: The Story of WikiLeaks, SVT"s documentary Wikirebels and VPRO"s de Wikileaks Code, as well as numerous television interviews.
In 2013 he left that role, but still serves as a board member of IMMI.