Age 15 · Coventry
PPLParty.com
Self-taught in code, I built a social network in my bedroom, aimed at young people and clubbers. It began as a way round the school firewall and spread by word of mouth.
Calum Brannan is a UK proptech entrepreneur. He taught himself to code, built his first social network at 15 and has been starting companies ever since. He founded Howsy, the digital lettings and property management business bought by Dexters in 2022, and is now co-founder and CEO of Supa, which brings AI to block management.
At 15, in Coventry, Calum built PPLParty.com, a social network for young people and clubbers that began as a way round the school firewall. By 18 it had passed 400,000 members, the business had moved into Electric Wharf in Coventry with a team of six, and he had spent a year as a product manager for Doug Richard, one of the original Dragons' Den judges. The Financial Times and The Guardian both profiled the business, and Director magazine named him Director of the Month.
With seed investors on board, PPLParty was rebuilt as Youmeo, a social media aggregator that grew to more than 500,000 users. Alongside it he co-founded Crowd Technologies, whose SoCrowd and CrowdControlHQ products sold social media risk management software to Cadbury, Experian, British police forces, the University of Greenwich, the BBC and TeamGB. The product was later acquired by BECG.
Calum founded Howsy in 2016 to make renting simpler for landlords and tenants. It won an Amazon Growing Business Award in 2017, and Calum was shortlisted for Start-up Director of the Year at the Institute of Directors in 2018. In 2019 Howsy raised £5 million and acquired online letting agent Urban.co.uk, and in 2020 it was named Best Lettings Agency at the Property Reporter Awards and bought the Upad brand, technology and landlord list out of liquidation. In 2021 it let and managed more than 6,000 properties with a team of around 100 across three offices, and Forbes named it a PropTech company to watch. Dexters acquired Howsy in 2022.
Supa, co-founded in 2025 with Alexis Johnson, buys established local block managing agents, keeps their names and their people, and gives them AI software that handles repair scheduling, safety checks and contractor coordination, so managers can spend their time in buildings. It looks after more than 20,000 homes across seven agents and announced a £21 million seed round in November 2026, co-led by 2150 and OpenOcean.
Calum writes about AI-enabled roll-ups on Medium. You can reach him on LinkedIn and X (Twitter).
Welcome to the building
Calum Brannan
Twenty years of startups under one roof. Come in, the lift is through the lobby.
Calum Brannan
Press the button to call the lift.
First floor · Lounge
I taught myself to code, built a social network in my bedroom at 15 and have been starting companies ever since. The notices below tell it in order.
Age 15 · Coventry
Self-taught in code, I built a social network in my bedroom, aimed at young people and clubbers. It began as a way round the school firewall and spread by word of mouth.
2007 · Age 18
The site passed 400,000 members and the business moved into Electric Wharf in Coventry with a team of six. I also spent a year as a product manager for Doug Richard, one of the original Dragons' Den judges.
2007 · Press
The FT and The Guardian both profiled the business when I was just 18, and Director magazine named me Director of the Month.
2008
With seed investors on board, PPLParty was rebuilt as Youmeo, a social media aggregator that went on to more than 500,000 users.
Crowd Technologies
Social media risk management software for large organisations, sold to Cadbury, Experian, British police forces, the University of Greenwich, the BBC and TeamGB. The product was later acquired by BECG.
2016 to 2022
A digital lettings and property management business that grew to more than 6,000 properties, won Best Lettings Agency in 2020 and was bought by Dexters in 2022.
Lift to B for the museum.
In between
Consulting for startups at every stage, with a focus on founders, funding and culture.
2025 to today
Co-founded with Alexis Johnson to modernise how blocks of flats are managed. It raised a £21 million seed round in November 2026.
Lift to R for the roof.
Basement · Museum
A digital lettings and property management business, founded in 2016. It grew to more than 6,000 properties and a team of 100 across three offices, and was bought by Dexters in 2022.






Penthouse · Roof terrace
Supa is what I am building now, co-founded in 2025 with Alexis Johnson. We buy established local block managing agents, keep their names and their people, and give them AI software that takes the admin off their desks.
£21m
Announced in November 2026. Co-led by 2150 and OpenOcean, with KOMPAS VC, Actia and Heartfelt, alongside a debt facility.
20,000
Across seven local managing agents acquired so far, each still trading under its own name.
AI
The software handles repair scheduling, safety checks and contractor coordination, so managers spend their time in buildings.
Residents are paying more every year and too often getting less.