Observe - offline, cross-platform field mapping tool for OpenStreetMap
2019-09-21 , Hörsaal Ost

Over the last few months, we’ve been building an offline first field mapping tool for the OpenStreetMap ecosystem called Observe. Observe makes field surveying, and verification easy for mappers, and works on iOS and Android. My talk will cover how Observe integrates with mapping workflows and helps improve OSM data from the field. I'll also touch upon fundamentals of building Observe and our assumptions on field mapping.


Field verification is an important part of keeping OSM data accurate. So far, field mapping exercises are largely manual, cumbersome, or requires internet connectivity. OpenStreetMap has an active mobile editing ecosystem, but they don't offer the same editing experience as iD for beginners. Most often mapping campaigns need an equally good tool that allows edits from the field to verify existing data and improve data quality.

Observe is a cross-platform, offline-first field mapping tool for OpenStreetMap, perhaps the first of its kind. Our primary goal was to build an application that makes field observation easy, and provide comparable experience to iD on Android and iOS — with some success. Observe focuses on browsing OSM data, and allows users to add new points, or verify existing information. The edits made offline are stored on the phone, and uploaded when the mapper goes online. Observe is a product of several iterations of user research and a couple of years of conceptualization.

The talk will:

  • introduce motivations behind building Observe
  • look at some specific use cases in campaign management
  • share internals of building the application
  • discuss challenges around offline editing and our approach to conflict resolution
  • gather feedback and launch a developer edition of the application

Subtitle Co-authors Talk keywords

mobile, field survey, offline mapping

Sajjad is leads the map data team at Development Seed. He contributes to their strategy for working with organizations like Humanitarian OpenStreetMap Team. Sajjad cares deeply about the impact open tools and data have on governance and development. Previously Sajjad helped build Mapbox’s data team and led products for mapping and validation. Sajjad has experience building platforms for natural resources monitoring and data infrastructure for large scale accountability initiatives. He's been making and talking about maps for over a decade. Sajjad is based in Bangalore and is actively involved in the open data movement in India.