Formulus

Open Data Ensemble | Internet

5 Downloads 15 Views v1.3 28 MB 4.1+

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(28 MB)

Editor's Overview

Formulus is a internet application developed by Open Data Ensemble, packaged as a single Android APK of version 1.3 weighing in at 28 MB. The package targets Android 4.1+ and above. Below you'll find the publisher's own description, a quick spec sheet, and a short buyer-beware checklist so you know exactly what you're installing before tapping download.

Install Checklist

Only download through the button on this page — never from third-party mirrors or shortened links, which are the most common way malware spreads.
File size is a light 28 MB, so it installs quickly even on modest connections.
This build is signed by "Open Data Ensemble" — always verify the developer name matches what's listed on the app's official store page before installing an update.
After install, Android may prompt you to allow "Install from unknown sources" — approve only this one install, then revoke the permission in Settings > Apps > Special access.
We link directly to the APK file or the publisher's repository; we do not modify the binary. Always run a virus scan after any sideloaded install.

About this app

Formulus is the mobile data collection client of the Open Data Ensemble (ODE) platform.

It allows organizations, research teams, and public sector institutions to build their own bespoke data collection applications based on structured forms defined using the JSONForms specification.

Forms and application logic are defined externally, meaning the same Formulus app can host many different data collection projects without requiring app updates.

Key features include:

• Flexible form-based data collection using JSONForms
• Offline-first operation for use in the field
• Secure bi-directional synchronization with an ODE Synkronus server
• Support for complex data structures and validation
• Designed for long-term maintainability and open standards

Formulus is particularly suited for environments where reliable data collection is needed under challenging conditions, such as:

• field research
• public health surveillance
• environmental monitoring
• humanitarian and development projects
• decentralized data collection initiatives

The app requires access to an ODE Synkronus server for synchronization and project management. Organizations typically run their own Synkronus server to host forms, manage users, and collect submitted data.

If you do not yet have access to a Synkronus server but would like to explore the application, a public demonstration environment may be available. See the project website for details.

Formulus is part of the Open Data Ensemble ecosystem, an open-source initiative focused on building interoperable tools for decentralized, standards-based data collection.

Source code and documentation:
https://opendataensemble.org

Details

Version	v1.3
Size	28 MB
Developer	Open Data Ensemble
Category	Internet
Package	org.opendataensemble.formulus
Android	4.1+
Last Updated	Oct 29, 2026
Downloads	5

Frequently Asked Questions

Is Formulus free to download?
Yes. The APK file linked from this page is free. The developer may offer in-app purchases once installed, but obtaining the installer itself costs nothing.

What Android version does Formulus require?
Android 4.1+ or newer. Installing on older devices may cause crashes or refuse to install.

Is Formulus safe to install?
We link to the exact APK published by Open Data Ensemble. We do not modify the file. Still, as with any sideloaded app, scan it with a reputable antivirus before opening it, and only grant permissions the app genuinely needs.

How do I update Formulus?
Install the newer version on top of the old one — Android will keep your data. If the signature differs, uninstall first (you may lose local progress).

Why is the app not installing?
Common causes: not enough storage, an older Android version than 4.1+, or a conflicting build already installed. Free up space, check your OS version, and uninstall any previous copy before retrying.

How to Download & Install Formulus

Tap the Download APK button above and save the file to your device.
Open your device Settings → Security (or Apps → Special access → Install unknown apps) and allow your file manager or browser to install unknown apps for this one file only.
Open the downloaded org.opendataensemble.formulus.apk file from your Downloads folder.
Tap Install and wait for Android to finish.
Open «Formulus» by Open Data Ensemble and grant only the permissions it actually needs.
Revoke the "unknown sources" permission once you are done installing.

Note: this page hosts or links to the installer only. The application name, icon and description are provided for identification. All trademarks belong to their respective owners.