Android app for predicting crowd levels at destinations and suggesting less crowded alternatives based on user preferences. Built by a team of five across two hackathons.
🥇 1st place — AI Hackathon 2026 — Open Track Organized by ACE @ AUEB ("ΟΠΑ"), Athens (March 2026).
🥇 1st place in the Greek round — Cassini Hackathon Greece 2025 Organized by Impact Hub Athens (December 2025). The team advanced to the European final and did not podium there.
Crowdless tells users how busy a destination is likely to be and offers alternatives that match their interests. The original Cassini brief was satellite data + GNSS for tourism sustainability; the team's pitch extended that into a consumer-facing app.
For the AI-Hackathon Open Track in 2026 the team rebuilt the app with stronger AI features around the same idea — "an AI-powered app that informs users about crowd levels and suggests alternative places based on their preferences" (organizer's description on the winners post).
The rebuilt AI-Hackathon version lives on a teammate's repo: https://github.com/EXARTeo/Crowdless_App (private — ask the owner for access).
This repo holds the Cassini-era Android client (Kotlin, single- activity) — the engineering footprint of the first hackathon, not the polished AI-ΟΠΑ winner.
The wins were team wins: pitch, business case, and presentation carried more weight than the code. The team built much that isn't here — the deck, market research, the rebuilt 2026 version.
Same five people across both hackathons:
- Alexandros Gkiafis (@AlexTuring010) — Android client (this repo)
- Theodoros Exarchos (@EXARTeo) — AI-Hackathon rebuild
- Mariglena Reci
- Stelios Rotas
- Panagiotis Thivaios
Mentor at Cassini: George Mendrinos.
- Platform: Android, Kotlin
- Build: Gradle (Kotlin DSL)
- Architecture: Single-activity
(
app/src/main/java/com/example/crowdless/MainActivity.kt, layout inapp/src/main/res/layout/activity_main.xml)
./gradlew assembleDebugInstall the APK from app/build/outputs/apk/debug/ to a connected
Android device, or open in Android Studio and run.
- Crowdless project page: https://www.linkedin.com/company/crowdlessapp/
- AI Hackathon 2026 winners (organizer's post): https://www.linkedin.com/posts/aihackathon2026-opentrack-innovationecosystem-ugcPost-7436487613802381312
- Cassini Hackathon Greece 2025 European-final recap (mentor George Mendrinos): https://www.linkedin.com/posts/georgemendrinos_yesterday-was-the-european-final-the-team-ugcPost-7394692583706468352
- Prior year of the AI ΟΠΑ Hackathon series (different team makeup, different challenge, didn't win): https://github.com/AlexTuring010/novibet-clone
MIT — see LICENSE.