Architectural and Usability Challenges in Designing a Unified Mobile Journey Planner Using Open Public Transport APIs in Finland
Rykov, Timofei; Vasiak, Denys (2026)
2026
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Julkaisun pysyvä osoite on
https://urn.fi/URN:NBN:fi:amk-2026052616837
https://urn.fi/URN:NBN:fi:amk-2026052616837
Tiivistelmä
Public transport plays the main role in city mobility, however regional transport authorities work independently in separate areas. This structural fragmentation leads to extra cognitive load for intercity travelers, as they are forced to use multiple applications/services to complete a single journey. To address this problem, nationwide mobile application prototype for public transport route planning in Finland was designed and developed, exploring the feasibility of merging regional and long-distance data streams into a unified Android application.
Implementation was carried out by following the Research-Based Design framework. Clean Architecture and Model-View-ViewModel patterns were utilized using Kotlin and Jetpack Compose to isolate business logic from the platform-dependent code. API integration was achieved by utilizing the Digitransit platform to aggregate static routing data in the GTFS format with the help of GraphQL alongside real-time tracking via binary Protobuf streams in the GTFS-RT format.
A functional Android application prototype was successfully developed, supporting unified intercity routing and real-time vehicle tracking for selected test regions. Final evaluation data was gathered through a combination of technical comparison analysis and user testing sessions using a free-form questionnaire and "Think Aloud" methodologies. The evaluation demonstrated that the modular framework successfully supported multi-city integration without requiring separate codebases for different transport providers. It was concluded that leveraging open transport standards within a layered, scalable architecture effectively minimizes regional fragmentation, significantly lowering the cognitive loads associated with inter-regional travels.
Implementation was carried out by following the Research-Based Design framework. Clean Architecture and Model-View-ViewModel patterns were utilized using Kotlin and Jetpack Compose to isolate business logic from the platform-dependent code. API integration was achieved by utilizing the Digitransit platform to aggregate static routing data in the GTFS format with the help of GraphQL alongside real-time tracking via binary Protobuf streams in the GTFS-RT format.
A functional Android application prototype was successfully developed, supporting unified intercity routing and real-time vehicle tracking for selected test regions. Final evaluation data was gathered through a combination of technical comparison analysis and user testing sessions using a free-form questionnaire and "Think Aloud" methodologies. The evaluation demonstrated that the modular framework successfully supported multi-city integration without requiring separate codebases for different transport providers. It was concluded that leveraging open transport standards within a layered, scalable architecture effectively minimizes regional fragmentation, significantly lowering the cognitive loads associated with inter-regional travels.