ODK Collect
ODK Collect is an open-source Android app for offline mobile data collection using XLSForm-based forms, written in Kotlin. It has been used to gather billions of data points and is a core field-data tool for African health, agriculture, election-monitoring and research programmes. It is Apache-2.0 licensed and actively maintained by the ODK community.
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Data collection
Verified Jul 2026Free / open-source