In 1998, Mathew cofounded the New York Taxi Workers Alliance (NYTWA), along with Bhairavi Desai, Javaid Tariq, and several others.
Perhaps its most historical campaign came in November 2021, when, after three years of direct action, including 15-day Hunger Strike, they reached an agreement with the City of New York and Marblegate Asset Management to restructure medallion mortgages, thereby saving many workers from falling into irretrievable debt.
In January 2020, Mathew cofounded the International Alliance of App Based Transport Workers (IIATW), along with delegates from 23 countries.
He is most recently the cofounder and chair of the executive council of Lamakaan, an open cultural space in Hyderabad, India.
After the 2002 Gujarat riots, in which Hindu groups killed over 2,000 Muslims, Mathew and several others founded the Campaign to Stop Funding Hate (CSFH), which tracked over US$6,000,000 being funneled to the Hindutva movement in India.
[7] ICWI has mounted campaigns to hold Facebook responsible for hate speech on its India platforms, fight for the release of the activists detained as part of the Bhima-Koregaon conspiracy, among others.
Mathew has authored numerous scholarly as well as journalistic publications on subjects ranging from labor to neoliberalism to communal violence.
[11] Between 1999 and 2011, Mathew hosted a weekly radio show for the WBAI station titled "Global Movements, Urban Struggles.