TextNow, a phone replacement app cofounded by CEO Derek Ting, is the biggest Waterloo success you’ve never heard of.

They’re enjoying a ton of momentum, with seven million monthly active users and a new office in San Francisco, so We Built This was eager to catch up with Ting to find out how TextNow works and where it’s headed.

We also spoke to Atom Factory founder and CEO Troy Carter about why he has invested, and the potential he sees in the company.

We Built This is a video feature from Communitech that shines a spotlight on technology entrepreneurs and their innovations in Waterloo Region, Canada.