1. ustwo
ustwo is one of London's most recognisable digital product studios, founded in Shoreditch in 2004.
They're best known as the creators of Monument Valley, but the studio side of the business builds digital products for clients across automotive, financial services, healthcare, and consumer tech.
Past clients include Ford, Google, and the NHS. With around 260 employees across London, New York, Malmo, Lisbon, and Tokyo, they operate more as a strategic design consultancy than a traditional dev shop. That makes them a strong fit for complex, high-stakes projects where product strategy matters as much as the build itself.
- Website: ustwo.com
- Clutch: clutch.co/profile/ustwo-studio
- Founded: 2004
- Team size: ~260 employees (global)
- Location: 154-158 Shoreditch High Street, London E1 6HU
- Best for: Enterprise-scale digital product strategy and design
2. Stakk
Stakk is an award-winning app development agency specialising in Flutter, React Native, iOS, and Android.
Based in the City of London, their team of 30+ certified engineers has delivered 150+ projects for clients including the British Museum, LNER, Sotheby's, Amazon, Samsung, and Disney. Projects range from around £10,000 to £300,000+ depending on complexity.
They're a strong mid-market option for brands that want a technically proficient team with recognisable case studies and transparent pricing.
3. Glance
Glance positions itself as the UK's most trusted app development agency, with a psychology-driven UX methodology that sets it apart from more technically led shops.
Their clients include Chanel, BAFTA, The Times, Canon, Universal Music, Lucozade, and the Ministry of Defence, with multiple apps reaching #1 on the App Store and 10M+ combined downloads.
They publish their pricing transparently on their site: MVP builds start at £10,000, professional projects at £50,000, and enterprise work at £120,000+. A distributed team across UK cities, but London-rooted.
- Website: thisisglance.com
- Clutch: clutch.co/profile/glance (15 reviews)
- Founded: 2016
- Project range: £10K - £120K+
- Notable clients: Chanel, BAFTA, The Times, Canon, Ministry of Defence
- Best for: Consumer-facing apps where UX and psychology-driven design are priorities
4. Magora
Magora is a Shoreditch-based agency that has delivered over 300 mobile app projects since 2010.
With 150+ employees, they're one of the larger dedicated app development shops on this list. They work across healthcare, finance, logistics, and entertainment, with project budgets ranging from roughly $65,000 to $650,000.
Clutch has ranked them among the top 3 mobile app developers in the UK, with 70 verified reviews. Their Tea Building address puts them in the heart of London's tech district.
5. Steer73
Steer73 is a full-service digital agency on Great Portland Street that handles mobile apps, custom software, web platforms, and data analytics.
Founded in 2014, their team of 40+ serves SMEs through to enterprise clients, with Paddy Power, Chubb, and DHL among their roster.
They're not a mobile-only shop, which makes them a practical choice for companies that need a single agency to handle their full digital stack rather than working with separate specialists for each channel.
6. GoodCore Software
GoodCore is one of the longest-running software development companies on this list, founded in 2005 and based in Croydon (Greater London).
They hold a perfect 5.0 rating on Clutch across 31 verified reviews and have been named to Clutch's Global 1000 list. Their average client engagement runs 6.8 years, which speaks to the quality of their ongoing relationships.
They use a hybrid onshore/offshore model with development centres in Malaysia and Pakistan, which helps keep costs competitive. Project budgets range from $10,000 to over $1 million.
7. Appy Monkey
Appy Monkey is a mobile app development studio in Mayfair that builds iOS and Android apps from concept through to launch and ongoing support. They also have offices in Newcastle and Manchester.
Clutch recognised them as one of the UK's leading mobile app developers in 2022. Their typical project budgets run around £25,000-£30,000, putting them in an accessible mid-range for startups and growing businesses.
If you want a London agency with a dedicated mobile focus rather than a full-service digital shop, Appy Monkey fits that brief.
8. Planes Studio
Planes Studio is a digital product studio in Hackney that builds and launches mobile and web products. Their recent portfolio includes the Allbright app, Skin Rocks (Caroline Hirons' skincare platform), and Slice Mobile (Lyca's digital-only network). They also work with NatWest and Accor.
They've repositioned recently as an "AI-native" product studio, which means they're integrating AI into the development process and the products themselves. A good option for brands building mobile products where AI capabilities are part of the value proposition.
9. Ostmodern
Ostmodern is a London-based creative technology company founded in 2006 that specialises in media, broadcast, and sports digital products.
With 50+ employees across eight countries, they build apps and streaming platforms for entertainment and media brands. They raised £2 million to fund international expansion, signalling real growth momentum.
If your app involves video, live content, or media delivery, Ostmodern has deep domain expertise in that space.
- Website: ostmodern.co
- Founded: 2006
- Team size: 50+ employees
- Best for: Media, broadcast, and sports streaming apps
10. Instinctive
Instinctive is a multi-award-winning app agency on London's South Bank, founded in 2006.
With over 14 years of experience, they build native iOS, Android, and progressive web apps for funded startups and established businesses. They're part of the Plug & Play (UK) Group, giving them connections to the wider startup ecosystem.
A solid option for founders and product teams who want a London-based agency with deep mobile experience and a focus on product-market fit.
- Website: instinctive.agency
- Founded: 2006
- Location: South Bank, London
- Best for: Startups and product teams building mobile-first products
11. Milo Creative
Milo Creative is a small specialist studio in London that has been building digital products since 2001, making them one of the most experienced teams on this list.
They hold a 5.0 Clutch rating and work across the full product lifecycle from strategy through to development. Their sweet spot is React Native apps, gamification, health apps, and education platforms.
With a small team (2-10 people), they offer a more personal, hands-on experience than larger agencies, at an hourly rate of roughly £100/hr.
12. Red C London
Red C is one of the longest-running app development agencies in London, founded in 1997. They've built over 200 mobile apps for iOS and Android across their 25+ year history.
Their Clutch rating sits at 4.6/5 with hourly rates in the $50-$99 range, making them a cost-effective option by London standards. A reliable choice for companies that value longevity and track record over flashy branding.
Final Thoughts
There we have the best options if you're looking for a mobile app developer in London.
But do you really need a mobile app developer at all? If you have a successful ecommerce store with a mobile-friendly website, spending £50-100K+ on a custom app from a London agency is likely overkill.
You don't need anything brand new in your mobile app. You just need the same user experience from your website, converted into a mobile app. That's what MobiLoud does. MobiLoud lets you launch an app significantly faster, and more cost-effectively, than any app development agency.
Curious if this is the right way to launch your app? Get in touch and book a free consultation to talk it over with our app experts.
