Top Web App Development Agencies in Seattle

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Top Featured Web App Development Agencies

Tallium Inc.
5
(11 reviews)
Fuelled by Excellence. Trusted by Leaders.
Tallium is a trusted partner for product co-creation, taking ideas from concept to award-winning apps through AI-native development and long-term collaboration. We help companies in fintech, edtech, healthtech, retail, logistics and beyond shape, design and build web, mobile and AI products. Our product leaders, senior designers and AI-native software engineers work as one team. We get to know your business and shape the product with you, and then the same team designs, builds and grows it. Everyone on your project is a Tallium employee, and the same people stay with your product for years. You can start with a focused proof of concept to test the idea, show investors or win your first customers with limited risk. As the product gains traction, we grow it into a full product team, and the engineers who already know your code bring new people up to speed. With AI-first engineering, AI agents handle routine coding within the standards we set for your project, and a named senior engineer approves every merge. The same budget covers more of your roadmap. If you can’t share code with an AI model, we use our classic process instead. 120+ people since 2012. Headquartered in Amsterdam, with R&D centers in Kyiv and Rzeszów.
9 works in Web Application
Located in Amsterdam, Netherlands
From €5,000 for Web Application
Worked in Media (+8)
Speaks English, Polish(+4)
51-200 members
BOX
(0 review)
BOX Internet Services – Custom Websites & Web Applications
BOX Internet Services develops professional custom websites and web applications for businesses, associations, and organizations. With over 20 years of experience in web development, we create user-friendly, reliable, and technically advanced solutions tailored to our clients' specific needs. From professional business websites to complex database-driven applications, BOX specializes in custom development using PHP, MySQL, and modern web technologies. Our expertise includes: - Custom Website Development – Professional business websites with tailored content management systems. - Web Applications – Customer portals, management systems, and custom online solutions. - Membership Management – Integrated solutions for associations, federations, and membership-based organizations. - Registration & Booking Systems – Online registrations, event management, and payment processing. - Database Development – Advanced database-driven websites and applications. - Web Hosting & Maintenance – Reliable hosting, technical support, and ongoing maintenance (only) for our projects. Personal service is at the heart of everything we do. At BOX, you work directly with the developer, without account managers or unnecessary intermediaries. This allows us to combine the flexibility of an independent specialist with the technical expertise required for larger and more complex projects. We don't build generic websites based on standard templates. Instead, we develop solutions that fit your business, meet your specific requirements, and grow alongside your organization. Looking for an experienced and reliable partner for your next website or custom web application? Contact BOX Internet Services to discuss your project and discover how we can help bring your ideas to life.
8 works in Web Application
Located in Aartselaar, Belgium
From €5,000 for Web Application
Worked in Sports (+10)
Speaks Dutch, English
1-10 members

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