- Square cofounder Tristan O'Tierney died Feb. 23 at age 35 from causes relating to addiction, the San Francisco Chronicle reported.
- O'Tierney, who worked at Square from 2009 to 2013, built the original iPhone app at Square, the mobile payments company.
- In the last years of his life, he pursued photography as a hobby and for work, traveling around the world and sharing his work on Instagram.
- Here's what people are saying on Twitter.
Square co-founder Tristan O'Tierney, who develop Square's original mobile payment app, passed away Feb. 23 in Ocala, Florida at age 35, the San Francisco Chronicle reported.
O'Tierney joined Square in February 2009 and built the original iPhone app as the head developer. He was the third co-founder of Square alongside Jack Dorsey and Jim McKelvey. Prior to that, O'Tierney had worked at companies like VMware, Apple, and Yahoo. O'Tierney left Square in June 2013.
Since leaving Square, he has done freelancing app development, worked as Director of Mobile for Voteraide, and pursued photography. He spent time traveling and doing photography both as a hobby and as a freelancer.
O'Tierney's family told San Francisco Chronicle that he died from causes relating to addiction, and they are awaiting an official cause of death from officials. He had been battling addiction for three years and was in a three-month rehabilitation program in Ocala, his mother Pamela Tierney told the Chronicle. O'Tierney had previously shared some of his struggles with addiction on social media.
A memorial service for O'Tierney will take place in San Francisco in the next two to three weeks.
Business Insider has reached out to Square for a statement. Square's website does not mention O'Tierney.
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As an avid photographer, O'Tierney often posted his work on Instagram. Below is O'Tierney's last image he posted on his Instagram, taken in Kailua-Kona, Hawaii.
Here's what people have been saying on Twitter.
This past week has been tough. @Tristan was a great mentor and friend to me in college, a super smart engineer who helped cofound Square, and had a sharp eye for design and as a photographer. Rest in peace, buddy. https://t.co/cjKF1aXeJv
- Steve Streza (@SteveStreza) March 1, 2019Met @tristan once. Had no idea who he was. Took me on a photo trip where he taught me even small cameras can take great photos. A gentle giant. pic.twitter.com/sSn6ax7p48
- Max "Tim Van Damme" Voltar [emoji] (@maxvoltar) March 1, 2019It being my first WWDC, and knowing really no one except my roommate and @tristan (from meeting in a line on the 1st day), I kept running in to him and talking his ear off about Mac dev. He was very kind / funny. Such a huge loss at such an early age. Addiction sucks.
- HWGIC (@sobossme) March 1, 2019So sad to hear about the passing. During my last WWDC trip in 2013, I met @tristan at @AltConference and fortunately had a chance to ask him for advices. I still remember those words. Thank you. https://t.co/EreSFBtw9w
- Richard Lee (@dlackty) March 1, 2019I met @Tristan when he was traveling around Asia after leaving Square - Square was headed to IPO then and he had so much to live for... so sad - RIP https://t.co/iZX0m7Qthv
- Jon Russell (@jonrussell) March 1, 2019A little bit of @tristan frozen in time on my original iPhone. Learnt so much from him building Twinkle together. Too young, too kind, and too talented to be gone so soon. RIP pic.twitter.com/v8AdPeDR5b
- Layton Duncan (@PolarBearFarm) February 28, 2019I am deeply saddened by the passing of my friend @Tristan. My profile picture was taken by him and is the best photo anyone has ever taken of me. I will miss him dearly.
- Robert Padbury (@padbury) February 28, 2019Sad to hear about @tristan. Back in the early days of @Square, he invited me to their office in the SF Chronicle building to hook me up with a card reader. He had my app on his phone and showed me how the antialiasing wasn't quite right. His attention to detail was inspiring. π
- ππππππ πΏπππππππ (@squeakytoy) February 28, 2019I did not know @tristan extremely well but recall the first time I met him at WWDC and I asked him what he did at Square. He answered so humbly and we had an amazing conversation. He was so loved by many; saddened to learn of his passing. #RIP
- David Hoang (@davidhoang) February 28, 2019Thanks, @tristan. Everyone at Square, and everyone Square's helped, owes a lot to your work.
- Jerry Lin (@jerrylin) February 28, 2019Only met @tristan once, way back in 2013 when I asked him to meet up at Sightglass just to chat about his recent travels and ask his advice on an app. He definitely had better things to do on a Tuesday afternoon. You wouldn't know it from all the time he gave.
- Andrew MacKenzie (@andrewmackenzie) February 28, 2019Can't believe @tristan has left us. Privileged to have gotten to work with him. Thank you for everything, dude.
- Kyle π³οΈβπ (@kyleve) February 28, 2019@tristan was a good friend and the ObjC dev community was lucky to know him and work with him. We're minus one good one.
- Bob Smith (@FriedLemur) February 28, 20191/ Incredibly sad to hear that my friend @tristan passed away this weekend.
He was a gifted photographer, engineer (cofounder of @Square and creator of @BarackObama's first campaign app) and a kind human.
- Tim Wagner (@wagner_tim) February 28, 2019A fond memory I have of @tristan: He wore a βS t-shirt to a WWDC '07 afterparty. Despite being a Mac user for many years prior, I didn't know what βS was. Needless to say he schooled me on it and made fun of me the rest of the night. I totally deserved it.
- Shane β‘οΈ Vitarana (@shanev) February 28, 2019So saddened to hear of the loss of @tristan. He was an exceptionally kind and gifted human. I will always fondly remember chasing light with you, friend.
- Sebastiaan de With (@sdw) February 27, 2019Saddened to hear of @tristan's passing over the weekend. I still remember building the first Square app together all of those years ago. He was always excited to build something new. Thank you for everything, Tristan. I'll raise a glass of whiskey for you. pic.twitter.com/tsjOO6Z1g2
- Robert Andersen (@rsa) February 27, 2019I only knew @tristan as a friendly conference peer from early iOS days. He was very friendly and approachable. Sad to hear he is gone. He will be missed by many. https://t.co/20Y41B0iOu
- Mike Zornek (@zorn) February 27, 2019What a terrible loss to the world. @tristan was one of the most creative people I knew. He was a great source of advice and encouragement in my early days of iOS development. He will be missed and will live on in his incredible photography. Sorry @mb. https://t.co/xvrzYRkqhs
- Shane β‘οΈ Vitarana (@shanev) February 27, 2019RIP @tristan. I didn't know him well, but we hung out a couple times in Portland and SF and shared some great photography chats. I'm no stranger to what we would consider 'an early death' but it never seems fair. π’ https://t.co/AxKjUZORUY
- Justin Miller (@incanus77) February 27, 2019I just heard the news about @tristan dying on Saturday. I didn't know him extremely well, but I'd known him for a decade, and we'd met several times. I'm in shock.
- Collin Donnell (@collindonnell) February 27, 2019Just heard that @tristan died last weekend. He was incredibly kind to @bcapps and I as we were getting our company off the ground. He always made time to check in whenever we were in the same city.
I'll miss him and the world will miss his photography. https://t.co/TooWDMZYVQ pic.twitter.com/ZNTUq6NCdp
- Matthew Bischoff (@mb) February 27, 2019I'm really shaken by the loss of @tristan. He did a lot in a short amount of time. Always good company. A lot of memories of better times. https://t.co/tQnRgbLuK0
- Sentius Magnus (@drance) February 27, 2019@tristan Thank you for helping me learn Objective-C. I don't think I'd be doing what I'm doing now if it wasn't for that. Thank you.
- Matt Zanchelli (@mdznr) February 27, 2019Really sad to hear that. Our paths crossed when we were both Mac Engineers in 2006. I keep really good memories of our discussions with @tristan and @thekarladam. https://t.co/8Xzx7CLWeH
- Jean-Daniel Guyot (@jdguyot) February 27, 2019Goodbye @tristan. You inspired me more than I ever told you. https://t.co/l4ofqT3gHI
- Kyle Kinkade (@kinkadius) March 2, 2019