# Pocket Science portfolio

Pocket Science builds and supports tailor-made citizen science apps, scientific instruments, data platforms and complete observatories for researchers worldwide.

This portfolio is evidence of four connected capabilities: translating research methods into understandable participant actions; attracting and supporting public participation; connecting apps to sensors, data and researcher workflows; and operating useful services beyond launch.

## Active flagship work

- [iSPEX](https://pocket.science/case-studies/ispex/) — Pocket Science built iSPEX1 for Leiden University and then took over iSPEX development. Ten thousand iSPEX1 instruments were produced and distributed for a nationwide Dutch citizen air-quality campaign. The resulting aerosol maps agreed with professional measurements and showed more local detail than satellite data where observations were dense. Plymouth Marine Laboratory successfully derived above-water remote-sensing reflectance with iSPEX2 in 2025. Research and validation continue; no units are currently available to order.
- [Black Hole Finder](https://pocket.science/case-studies/black-hole-finder/) — actively maintained astronomy observatory combining public classification, researcher workflows and machine-learning support. It was a SciStarter Top Ten project by participation in 2024 and was featured on the NRC front page on 30 April 2026.
- [Dark Sky Meter suite](https://pocket.science/case-studies/dark-sky-meter/) — Dark Sky Meter and Pro for iPhone, plus continued development of Loss of the Night for Android. Dark Sky Meter has received more than 50,000 measurements and remains actively supported.
- [Mini Secchi](https://pocket.science/case-studies/mini-secchi/) — an actively maintained physical water-observation method connected to mobile and web participant guidance and research data services, developed through Horizon 2020 MONOCLE.

## Complete project archive

The wider archive includes:

- [Transit of Venus](https://pocket.science/case-studies/transit-of-venus/) — made for Astronomers Without Borders to test whether worldwide smartphone observers could repeat the historic experiment for estimating the Earth–Sun distance; 130,000+ downloads and tens of thousands of submitted timings.
- Arctic March — sponsored by RIVM and following Berenice Nooteboom's polar research with iSPEX1.
- Aware Hero — mobile public-engagement application made for Oxfam.
- Digital Diversity Wheel — built for farmers in Zimbabwe and Uganda; sponsored by Oxfam and Wageningen University.
- MOBIS — one of the first citizen-science apps in the European Open Science Cloud catalogue; reusable mobile observation, offline collection, sensors and research services.
- MONOCLE — Horizon 2020 water-observation apps, sensors, campaigns and data.
- Run4Science — developed with COS4CLOUD, connecting runners, smartphones and environmental sensors.
- Mijn Hemel — Dutch mobile astronomy and sky-information application.
- Occultation — crowdsourcing the shape of a near-Earth object from observers timing a stellar occultation at different locations.
- TriAtlas — interactive astronomical atlas on mobile.
- Turfberg Radio Astronomy Monument — a location-based tribute to the history of Dutch radio astronomy.
- Zicht op Licht — public participation around artificial light, made for the University of Groningen.
- Seeing Stars Leiden — an app and shared data view supporting the 2022 citywide lights-out citizen-science experiment in Leiden.
- Dark Sky Meter IAU — the accessible public edition of Dark Sky Meter, sponsored by the International Astronomical Union.
- Loss of the Night — guided naked-eye star observations on Android; development continued from IGB by Pocket Science.

## Independent evidence

- [Nature: Technology — Smartphone science](https://www.nature.com/articles/nj7596-669a)
- [EGI: Boosting Citizen Science with Deep Machine Learning](https://www.egi.eu/case-study/cos4cloud/)
- [SciStarter / Discover: Citizen Science 2024 Wrapped](https://www.discovermagazine.com/citizen-science-2024-wrapped-46902)
- [NRC: De jacht op een zwart gat begint op je telefoon](https://www.nrc.nl/nieuws/2026/04/30/de-jacht-op-een-zwart-gat-begint-op-je-telefoon-a4925690)
- [Scientific American: 8 Apps That Turn Citizens into Scientists](https://www.scientificamerican.com/article/8-apps-that-turn-citizens-into-scientists/)

## Continuity

Pocket Science often continues where funded research projects stop. Apps still need updates, participants still need answers and data still carries value after a grant. That commitment also established a hard operating principle: continuity cannot depend on unlimited unpaid work. Ownership, maintenance, support and the route beyond funding should be designed and funded from the start.

Contact: [web@pocket.science](mailto:web@pocket.science)