|Headquarters||San Francisco, USA|
|Key people||Jeff Lawson (co-founder, CEO), Evan Cooke (co-founder, CTO), John Wolthuis (co-founder)|
Twilio is a cloud communications (IaaS) company based in San Francisco, California. Twilio allows software developers to programmatically make and receive phone calls and send and receive text messages using its web service APIs. Twilio's services are accessed over HTTP and are billed based on usage.
As of October 2012, more than 150,000 developers use the service.
Twilio's first major press coverage was the result of an application built by Jeff Lawson to Rickroll people, which investor Dave McClure used on TechCrunch founder and editor Michael Arrington as a prank. A few days later the company launched Twilio Voice, an API to make and receive phone calls completely hosted in the cloud. Twilio's text messaging API was released in February 2010, and SMS shortcodes were released in public beta in July 2011.
Twilio is known for its use of platform evangelism to acquire customers, and the most notable early success story from this approach is GroupMe, a company created in May 2010 at the TechCrunch Disrupt hackathon in New York City that uses Twilio's text messaging product to facilitate group chat and raised $10.6 million in venture funding in January 2011.
Following the success of the TechCrunch Disrupt hackathon Seed accelerator 500 Startups announced the Twilio Fund, a $250,000 "micro-fund" to provide seed money to startups using Twilio in September 2010.
Twilio has raised approximately US$33 million in venture capital growth funding. Twilio received its first round of seed funding in March 2009 for an undisclosed amount, rumored to be around $250,000, from Mitch Kapor, The Founders Fund, Dave McClure, David G. Cohen, Chris Sacca, Manu Kumar, and Jeff Fluhr. Twilio's first A round of funding was led by Union Square Ventures for $3.7 million and its second B round of funding was for $12 million was led by Bessemer Venture Partners. Twilio received $17 million in a Series C round in December 2011 from Bessemer Venture Partners and Union Square Ventures. In July 2013 Twilio received another $70 million from Redpoint Ventures, Draper Fisher Jurvetson (DFJ) and Bessemer Venture Partners 
Twilio follows a set of architectural design principles to protect against unexpected outages, and received praise for staying online during the widespread Amazon Web Services outage in April 2011.
Twilio supports the development of open-source software and regularly makes contributions to the open source community. In June 2010 Twilio launched OpenVBX, an open source product that lets business users configure phone numbers to receive and route phone calls. One month later Twilio engineer Kyle Conroy released Stashboard, an open source status dashboard written in the Python programming language that any API or software service can use to display whether their service is functioning properly or not. Twilio also sponsors Localtunnel, created by now ex-Twilio engineer Jeff Lindsay, which enables software developers to expose their local development environment to the public internet from behind a NAT.
Twilio was named to the "Dow Jones FASTech 50 Start-ups to Watch" list for 2010, The Business Insider named Twilio as one of "20 Hot Silicon Valley Startups You Need To Watch" in 2010, and Twilio received recognition as a Gartner "Cool Vendor" in April 2011. In February 2012, Twilio was named one of the most innovative companies by Fast Company 
- Twilio Raises $3.7 Million For Powerful Telephony API
- Twilio scores funding to build telecom in the cloud business
- Thanks Twilio, No One Is Safe From The RickRoll Now
- Twilio: Powerful API For Phone Services That Can Recreate GrandCentral's Core Functionality In 15 Lines Of Code
- Twilio's Telephony API Now Lets Applications Send And Receive SMS Messages
- Twilio's Streamlined Shortcode API Now Open To All
- Twilio’s Founder On How To Partner With 20,000 Developers – with Jeff Lawson
- Inception: A Hackday Dream (The Story Of GroupMe)
- Group texting startup GroupMe raises $10.6M despite being a long way from revenue
- Got a Twilio-based App? Get Some Investment Dollars
- Announcing Twilio Fund for 500 Startups
- Twilio Crunchbase.com Profile
- Twilio Closes Funding Round, Lands Major Customers For Its Telephony API
- Twilio Raises $12 Million For Powerful Telephony API
- Twilio Raises $17M Series C From Bessemer and Union Square to Expand Abroad
- Twilio Raises A $70M Series D As They Consider An IPO
- Why Amazon Will Make or Break Twilio
- Twilio's Cloud Architecture Principles
- Twilio Releases OpenVBX, An Open Source Google Voice For Businesses
- Twilio open sources Stashboard, an API monitoring dashboard
- Making a Local Web Server Public with Localtunnel
- VentureWire’s FASTech Conference Spotlights Most Promising Start-Ups
- 20 Hot Silicon Valley Startups You Need To Watch
- The World's 50 Most Innovative Companies