Most startups that build a mobile app first do so because the founder uses their phone for everything, an investor mentioned that 'mobile is where the growth is,' or the product demo looks more impressive on a phone. None of these are the right basis for a decision that will consume three to six months of runway.
The Actual Differences That Matter
Development cost: a Bubble web app with Supabase can be live in six to ten weeks. A native mobile app takes three to five months minimum. Update speed: web apps can be updated and deployed instantly. Mobile apps require app store approval cycles of one to three days. Hardware access: mobile apps have native access to GPS, camera, push notifications, offline functionality. Distribution: web apps are accessible via URL — no installation required.
Five Questions That Determine the Right Choice
1. Where does your user actually do the work? Desk-based work is done on a browser. Field work is done on a phone. 2. Does your product need offline functionality? 3. How frequently will users interact with it? Products used multiple times per day benefit from mobile home screen presence. 4. Is your user base technically sophisticated? B2B users are generally comfortable with web applications. 5. How fast do you need to learn? Web apps give faster iteration cycles for products in active discovery.
When Web Is the Right Starting Point
Build web first if: users work primarily at a desk, no hardware features required, still in active discovery, go-to-market is B2B, or need to be live within three months. This covers the majority of B2B SaaS, internal tools, client portals, dashboards, and workflow tools.
When Mobile Should Come First
Build mobile first if: users are doing field or moving work, product genuinely requires GPS, camera, or offline functionality, target market is consumer, or competitive landscape is primarily mobile apps.
A Real-World Example: Elena's Field Service Platform
Elena builds software for property maintenance companies in Spain and Portugal. Her initial product was a web app built in Bubble with Supabase in eight weeks, live with paying customers within three months. Twelve months later, with validated product-market fit, she added a mobile companion app for field technicians needing camera access and offline capability. By building web first, she validated the product and generated revenue before investing in mobile.
