A mobile check-in app is a specific type of project - narrower than a full HR platform, broader than a simple form. The core functionality covers five things: QR scan or GPS location capture, employee authentication, timestamp recording, a manager dashboard, and payroll export. Most teams underestimate the last two.
Three Tech Paths and Their Costs
Web app with camera and GPS API. A browser-based progressive web app runs on any smartphone without installation. Employees scan a QR code or confirm GPS through the browser. Build time: 4-6 weeks for an MVP. Cost: €6,000-10,000. The tradeoff: camera access varies across mobile browsers, and offline mode requires extra development.
React Native or Flutter. A single codebase deploys to both iOS and Android. Build time: 6-8 weeks for an MVP. Cost: €12,000-20,000. This path provides better device hardware integration than a web app and a native feel without the cost of two separate builds.
Native iOS and Android. Two codebases, best UX, highest cost. Build time: 3-4 months. Cost: €25,000 and above. Justified for teams with 500+ employees where friction in the check-in flow measurably affects adoption.
Three Mistakes That Delay Launch
Building the admin panel before the check-in flow. Teams focus on what managers see before solving how employees check in. The employee-facing interface is harder to get right and more likely to fail in real conditions. Build it first.
No offline mode for poor-signal sites. Construction sites, warehouses, and rural locations have inconsistent connectivity. An app that requires a live connection to record a check-in fails at the exact moment it needs to work. Offline-first design with background sync solves this but adds 2-3 weeks to the build.
Skipping employee UX for manager dashboards. A check-in flow that takes 5 steps when it could take 1 creates adoption problems from the first day. Target 15 seconds maximum for the employee-facing flow. If a 60-year-old warehouse worker can't complete it on first try, redesign it.
Ongoing Costs
An MVP is not the end. Server hosting, app store developer fees (Apple charges $99/year, Google charges $25 one-time), and maintenance for OS updates add €2,000-5,000 per year on a React Native or Flutter build. Factor this into the build-versus-SaaS comparison before starting.
Integration Is Where Projects Stall
The check-in flow takes 6 weeks. Getting that data into payroll takes another 4. Most build timelines underestimate the integration work at both ends: employee identity management on one side, payroll format on the other. Plan for it from day one rather than discovering it at the end.
Rezano as a Starting Point
Rezano is available as a SaaS platform or as the foundation for a custom build. For teams that need standard check-in functionality, the SaaS route is faster and lower-risk. For teams with workflow-specific requirements, the custom path starts from a working codebase rather than a blank file.