For Astronomers Without Borders
Transit of Venus
Could a worldwide crowd repeat the historic experiment for estimating the Earth–Sun distance? More than 130,000 people downloaded the app to take part.
Selected work · active and proven
Citizen science apps, instruments and observatories.
Work for researchers worldwide, spanning public participation, scientific sensing, data infrastructure, outreach and long-term support.
Built to be used.
The strongest thread through this portfolio is not a particular template or technology. It is the ability to turn a research method into something people understand, value and continue to use—while researchers receive the data, access and support they need.
Flagship instrument · air and water
iSPEX
iSPEX1 was built for Leiden University and enabled a nationwide citizen air-quality map with more local detail than satellite data where observations were dense. iSPEX2 later achieved successful above-water Rrs validation with Plymouth Marine Laboratory.
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For Radboud University · active observatory
Black Hole Finder
Public classification, researcher workflows and machine-learning support around live astronomical candidates. A SciStarter Top Ten project in 2024 and NRC front-page story in 2026.
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Owned product · active support
Dark Sky Meter suite
Dark Sky Meter and Pro for iPhone, plus continued development of Loss of the Night for Android. More than 50,000 Dark Sky Meter measurements and years of device calibration and support.
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Sponsored by Exeter and the Moore Foundation · actively maintained
Mini Secchi
An actively maintained physical water-observation method connected to participant guidance, mobile and web applications and a research data service, developed through Horizon 2020 MONOCLE.
Read the case study →Complete project archive
The rest of the work belongs here too.
Some were worldwide campaigns, some were research infrastructure, some were focused public apps and some were early experiments. Together they show the range behind today’s offer.
Sponsored by RIVM
Arctic March
iSPEX1 followed polar researcher Berenice Nooteboom into the Arctic, bringing smartphone measurement into an extraordinary field campaign.
For Oxfam
Aware Hero
A public-engagement app that made participation visible through personal action, progress and an inviting mobile experience.
Sponsored by Oxfam and Wageningen University
Digital Diversity Wheel
Farmers in Zimbabwe and Uganda could explore and record crop and food diversity through a practical field application.
Early EOSC catalogue service
MOBIS
A reusable observatory platform for apps, offline fieldwork, sensors and research services—and one of the first citizen-science apps in the EOSC catalogue.
Horizon 2020
MONOCLE
International water observation connected field campaigns, participant apps, low-cost instruments and research data across one programme.
Developed with COS4CLOUD
Run4Science
Runners became moving research participants, carrying environmental sensors while their smartphones connected activity, place and observations.
Astronomy
Mijn Hemel
Astronomy information designed for the phone in your pocket, helping a broad Dutch audience understand what was visible overhead.
Near-Earth object research
Occultation
Observers at different locations timed one disappearing star; together, their measurements could reveal the shape of a near-Earth object.
Astronomical reference
TriAtlas
Detailed astronomical charts became an interactive mobile reference that observers could carry into the field.
Heritage · public outreach
Turfberg Radio Astronomy Monument
A location-based digital layer brought the history of Dutch radio astronomy to life at the monument itself.
For the University of Groningen
Zicht op Licht
Citizens investigated artificial light with university researchers—and the experiment reached a national news audience.
Leiden · citywide citizen science
Seeing Stars Leiden
When Leiden switched off its lights, residents used Pocket Science apps and a shared map to record how the night sky changed.
Sponsored by the IAU
Dark Sky Meter IAU
An IAU-sponsored public edition put smartphone light-pollution measurement within reach of a worldwide astronomy audience.
Android · long-term support
Loss of the Night
Guided naked-eye observations turn visible stars into light-pollution data. Pocket Science took over and continues development from IGB.
How the work evolved
Each project added a capability.
The history matters because today’s offer grew from real launches, field campaigns, scientific problems and years of operation.
- 2012
Transit of Venus
The first Pocket Science app asked whether a worldwide crowd could repeat the centuries-old experiment for estimating one astronomical unit. It reached 130,000+ downloads and tens of thousands of submitted timings.
- From 2013
Dark Sky Meter
Phone-camera calibration, public light-pollution measurement, worldwide outreach and long-term product support.
- iSPEX1 · air quality
A nationwide citizen observatory
Built for Leiden University and developed onward by Pocket Science: 10,000 instruments distributed, thousands of citizens and a national aerosol map with local detail beyond the satellite comparison where measurements were dense.
- MONOCLE
Water methods and connected field work
iSPEX2, Mini Secchi and international field campaigns expanded the work into water observation and above-water radiometry.
- COS4CLOUD · EOSC
Observatory infrastructure
MOBIS became one of the first citizen-science apps in the European Open Science Cloud catalogue. Run4Science was developed with COS4CLOUD to connect mobile participation and environmental sensors.
- Continuing in 2026
Research services that stay alive
Black Hole Finder, Mini Secchi and the Dark Sky Meter suite are actively maintained. Black Hole Finder also shows how public participation, experienced users, machine learning and researchers can contribute to one living observatory.
Independent record
Seen far beyond our own websites.
Selected archival proof from international and national coverage. These are evidence of public reach, not decoration.
Beyond the grant
Useful science needs a continuation plan.
Research projects end. Apps still need updates, participants still need answers and data still carries value. Pocket Science has often continued where funded projects stopped.
That commitment also taught us a hard lesson: continuity cannot rest on unlimited unpaid work. Ownership, maintenance, support and the route beyond funding now belong in the project design from the start.
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