oliexdev

oliexdev/openScale

Kotlin GPL-3.0 Healthcare

Open-source weight and body metrics tracker, with support for Bluetooth scales

2.4k stars
457 forks
active
GitHub +17 / week

2.4k

Stars

457

Forks

10

Open issues

30

Contributors

AI Analysis

openScale is an open-source Android application for tracking weight and body metrics from Bluetooth-enabled scales, with support for 30+ scale models from manufacturers like Beurer, Xiaomi, and Yunmai. It serves health-conscious individuals and fitness enthusiasts who want privacy-respecting metric tracking without account creation. The project is not suitable for users requiring cloud synchronization, advanced medical analysis, or integration with proprietary fitness ecosystems.

Healthcare Application Discovery value: 5/10
Documentation 7/10
Activity 9/10
Community 7/10
Code quality 6/10

Inferred from signals mentioned in the README (tests, CI, type safety) — not a review of the actual code.

Overall score 7/10

AI's overall editorial judgment — not an average of the bars above, can weigh other factors too.

health-tracking bluetooth-integration android-mobile privacy-focused open-source
Actively maintained Well documented Niche/specialized use case Beginner friendly Production ready
Deep Analysis · Based on README and public signals
6d ago

Privacy-first Android weight tracker with Bluetooth scale support and offline-only operation

openScale is an Android app for tracking weight, BMI, and 15+ body composition metrics. It supports 50+ Bluetooth scale models from manufacturers like Beurer, Xiaomi, and Yunmai. The app operates entirely offline, stores no cloud data, and requires no account. Primary audience: users seeking privacy-respecting fitness tracking and people with non-standard body compositions. Adoption appears concentrated in privacy-conscious and open-source communities rather than mainstream fitness apps.

Origin

Created December 2014 as a personal project, openScale evolved into a mature open-source alternative to proprietary scale manufacturer apps. Built in Kotlin for Android, it has accumulated 12 years of feature additions and scale integrations driven by community feedback.

Growth

The project grew slowly but steadily, reaching ~2,400 stars by mid-2026. Recent activity (11 stars in last 7 days) suggests stable but modest ongoing interest. F-Droid and Google Play Beta availability indicate gradual adoption within privacy-conscious Android users. Growth pattern reflects niche positioning rather than explosive viral adoption.

In production

Present on F-Droid (privacy-respecting app store) and Google Play Beta. Multiple supported Bluetooth scale models suggest real hardware integration. Wiki documentation for supported scales indicates community-driven maintenance. Adoption not formally quantified—no public user metrics, download counts, or enterprise deployments documented. Likely used by individuals rather than organizations.

Code analysis
Architecture

Appears to be a native Android app written in Kotlin with Bluetooth LE (BLE) integration for scale communication. README indicates support for multiple metrics calculation, data export/import (CSV), user profiles, and widget functionality. Likely uses Android architecture patterns but specific architectural details not documented in README.

Tests

Not documented in README. CI badge present (GitHub Actions) but test coverage metrics not visible from provided metadata.

Maintenance

Last push July 3, 2026 (one day before analysis date) indicates active maintenance. CI/CD pipeline operational. Translation status widget suggests ongoing internationalization effort via Weblate. Release cadence not specified in README but dev builds available on GitHub releases. Maintenance appears regular and engaged rather than abandoned.

Honest verdict

ADOPT IF: you own a supported Bluetooth scale, prioritize privacy and offline operation, and want metric tracking without cloud vendor lock-in. AVOID IF: you need cloud sync across devices, smartphone ecosystem integration (HealthKit, Google Fit), or comprehensive fitness ecosystem features. MONITOR IF: you want multi-device sync—the openScale-sync companion project may mature to address this; also monitor Bluetooth 6+ scale support as new models emerge.

Independent dimensions

Mainstream potential

3/10

Technical importance

6/10

Adoption evidence

4/10

Risks
  • Bluetooth scale support depends on reverse-engineering manufacturer protocols; new scale models may not work until community adds support, creating user friction.
  • Android-only limits addressability; iOS users cannot use the app, reducing TAM.
  • Single-maintainer dependency risk evident from project structure; sustainability unclear if creator disengages.
  • Offline-only design prevents cloud backup; data loss if device is lost or corrupted without manual export.
  • No quantified user base or business model; funding appears donation-based and may be insufficient for long-term maintenance.
Prediction

Likely to remain a stable niche tool for privacy-conscious Android users and multi-scale households. Growth will depend on Bluetooth scale ecosystem evolution and privacy-conscious user cohort expansion. May gradually integrate with open-source health platforms but unlikely to reach mainstream fitness app adoption.

0 found this helpful

Newsletter

Get analyses like this every Monday

Free weekly digest of the most interesting open-source discoveries.

Languages

Kotlin
94.9%
C++
4.5%
Processing
0.3%
C
0.2%
Ruby
0.1%

Information

Language
Kotlin
License
GPL-3.0
Last updated
5d ago
Created
141mo ago
Analyzed with
anthropic/claude-haiku-4-5

Stars over time

Loading…

Contributors over time

Top 100 contributors only — repos with more will plateau at 100.

Loading…

Similar repos

clementwzk

clementwzk/OpenCalc

OpenCalc is a lightweight, open-source calculator application for Android with...

1.5k Kotlin Productivity
mtotschnig

mtotschnig/MyExpenses

MyExpenses is a GPL-licensed Android expense and income tracking application...

1.2k Kotlin Finance
BLE-Research-Group

BLE-Research-Group/MetaRadar

MetaRadar is an Android application for scanning, analyzing, and tracking...

1.5k Kotlin Security
markusfisch

markusfisch/BinaryEye

Binary Eye is a free, open-source barcode scanner and generator for Android...

2.3k Kotlin Mobile
the-momentum

the-momentum/open-wearables

Open Wearables is a self-hosted platform that unifies health data from multiple...

2.1k Python Healthcare
vs. alternatives
Google Fit / Apple HealthKit

Mainstream fitness ecosystems requiring cloud sync and accounts. openScale trades features for privacy and offline operation; incompatible use cases rather than direct competition.

Proprietary Bluetooth scale apps (Beurer, Xiaomi, etc.)

openScale consolidates multi-manufacturer support into one app; vendor apps lock users into single brands. openScale benefits users with multiple scale types.

Fitbit / Withings companions

Proprietary subscription-based ecosystems. openScale appeals to users rejecting cloud lock-in and subscription models.

MyFitnessPal / Cronometer

Full nutrition + fitness platforms. openScale narrower scope (weight/body metrics only); complementary rather than competitive.

Simple weight trackers (Happy Scale, Libra)

openScale distinguishes via Bluetooth scale automation and body composition metrics; competitors focus on manual entry simplicity.