Università di Bologna / Grin-Up
Tracking students’ mobility and consumption habits
Tracking students’ mobility and consumption habits
Mobile App • 2024 - 2025
An advanced iOS and Android mobile app to increase student participation in a PNRR research project.
An advanced iOS and Android mobile app to increase student participation in a PNRR research project.
The system turns scientific data collection on urban mobility into an engaging gamified experience, ensuring continuous GPS tracking while fully respecting privacy.
The University of Bologna needed to collect real, continuous data about students’ urban mobility.
Researchers had already involved thousands of students through traditional questionnaires, but to raise the bar they needed a tailored solution balancing scientific rigor, GDPR constraints, and a user experience able to keep engagement high beyond the first weeks of use.
Challenges as research units
Each Challenge consists of completing questionnaires and tracking personal mobility, and can last from a few days to several weeks. Through a back-office portal, the research team can create, publish, and orchestrate each Challenge, while the data collected by the app is sent to Qualtrics for analysis.
Periodic surveys
Each week of the Challenge corresponds to a new periodic questionnaire, sent automatically at the end of the tracking window.
Spot surveys
These are questionnaires sent at specific times to collect contextual data, for example regarding weekend purchases.
GPS tracking of mobility
Through GPS, the app monitors the user's travel areas and the mode of transport being used, notifying them for the entire duration the tracking is active. The exact location of the user is not sent, but rather an area around it, to guarantee privacy.
Key features of the system
Key features of the system
Gamification and leaderboards
Completing surveys and GPS tracking generates points, turning research into a virtuous competition.
Spatial cloaking
The app never sends exact coordinates. The GPS point is transformed into a polygon area (200–500m radius), allowing mobility flows to be studied without tracing back to the user’s exact address.
Back office for researchers
A dedicated web control panel that lets the university team orchestrate the entire system: configure new challenges, schedule survey delivery, and monitor data collection progress.
Smart scheduling
To avoid impacting battery life and privacy, users are assigned randomized tracking time windows (e.g. Monday morning or Wednesday afternoon).
Integration with university systems
The app automatically recognizes students already registered and integrates with Qualtrics for survey administration.
Points leaderboard in the app
App downloads during the first active challenge
1,900+
Responses to periodic and spot surveys collected by the system
8,000+
Completed and anonymized GPS tracks
875+
Beyond the numbers, the app reshaped the university’s research method: from static questionnaires to continuous tracking. The gamification system kept students interested over time, while on-device anonymization ensured maximum security without sacrificing data quality.
How Might We Questions
The project started with an initial discovery phase to map the research team’s needs, regulatory constraints, and students’ expectations around privacy and usability. We then built a technical PoC to validate the most critical aspects: battery life and data anonymization.
Development happened in iterative cycles, with progressive releases that let us test specific features and continuously gather feedback. Before the full rollout, we ran intensive user testing with a small group of researchers and volunteer students, refining onboarding flows, push notifications, and location-permission management.
Architecture, cloud, and privacy-by-design
The infrastructure is cloud-native on AWS with serverless logic (ECS Fargate), ensuring automatic scalability during participation peaks and controlled operating costs. The backend is based on Directus, used as an API layer and administration interface for the researchers’ back office.
We adopted a zero-trust approach. To maximize protection, anonymized GPS data doesn’t even pass through our database: the app sends it directly to the University’s protected systems via encrypted connections.
Flutter development allowed us to manage, with a single codebase, the complexities of motion sensors and GPS tracking across both iOS and Android.