Senior Ionic/Cordova Developer Needed to Diagnose and Fix Android QR Scanner Camera Issue
PROJECT DESCRIPTIONOverview
We have a legacy mobile application built with Ionic 3, Angular, and Apache Cordova. The application is used to scan QR-code tickets at live events and festivals.
The app builds successfully as a debug APK, and authentication works correctly. However, when the user opens the scanner, the camera preview remains blank and the QR scanner does not initialize.
We have already completed extensive investigation, including plugin changes, configuration updates, WebView rendering experiments, native Android modifications, and multiple test builds. The issue remains unresolved.
We are looking for an experienced Cordova specialist who can diagnose the root cause and implement a reliable fix.
Full investigation notes will be provided to the selected freelancer to prevent duplicated work.
The Issue
The scanner screen calls the QR scanner plugin to initialize the device camera behind a transparent Cordova WebView.
In the current Android build:
- The scanner screen opens, but the camera preview does not appear.
- QR scanning does not begin.
- The application does not crash.
- Previous native rendering and configuration changes produced no visible improvement.
A known working version of the application is available for comparison.
Scope of Work
The selected developer will:
- Diagnose why the QR scanner and camera preview are not initializing.
- Review the Cordova plugin registration, JavaScript bridge, Android lifecycle, runtime permissions, and native camera implementation.
- Use ADB logcat and other appropriate Android debugging tools to identify the failure.
- Implement a reliable fix in the existing Ionic/Cordova application.
- Confirm that the scanner opens and reads QR codes correctly on Android 11 or later.
- Document the root cause and all changes made.
- Submit the completed fix through a pull request.
This engagement is specifically for repairing the current Cordova implementation. A migration to another framework is outside the immediate scope.
Current Technology Stack
ComponentVersionUI frameworkIonic 3JavaScript frameworkAngular 7Native bridgeApache CordovaAndroid platformcordova-android 14.0.1Target SDKAndroid API 35Compile SDKAndroid API 35QR scannerCustom fork of cordova-plugin-qrscannerLocal storageLocalForage / Ionic StorageInternationalization@ngx-translate/coreLanguagesEnglish and French
Required Experience
Applicants must have strong practical experience with:
- Apache Cordova plugin architecture
- plugin.xml, <js-module>, <config-file>, and cordova.exec()
- Cordova JavaScript-to-native bridge debugging
- Ionic 3 and Angular TypeScript debugging
- Android runtime camera permissions
- Android native camera integration
- Camera2 or similar Android camera APIs
- Cordova WebView transparency and native view layering
- ADB and logcat diagnostics
- Android Gradle configuration
- AndroidX and modern Android SDK compatibility
Preferred Experience
The following experience would be valuable:
- Previous work with cordova-plugin-qrscanner
- Experience repairing or modernizing abandoned Cordova plugins
- Barcode or QR scanning integrations in Cordova applications
- WebView hardware and software rendering layers
- Ionic-to-Capacitor migration experience
- iOS Cordova camera troubleshooting
Deliverables
The engagement will be considered complete when the following are delivered:
- A working debug APK in which the QR scanner camera opens correctly.
- Successful QR-code scanning on an Android 11 or later test device.
- A documented code fix submitted through a GitHub pull request.
- A written diagnostic report explaining:
- The root cause
- How the issue was identified
- What code or configuration was changed
- Any limitations or future maintenance concerns
- Clear build and testing instructions.
- Confirmation that the updated source code builds successfully.
Access Provided
After the freelancer has been selected and the engagement has started, we will provide:
- Access to the relevant source-code repository
- A controlled GitHub workflow for submitting changes
- Test-device details
- Logs and diagnostic information
- Notes from our previous investigation
- Access to a known working application version for comparison
No production credentials or unnecessary customer information will be shared.
Important Notes
This is a legacy application using Ionic 3 and Cordova. We understand that both technologies are outdated, and we have a longer-term plan to rebuild the application using a more modern architecture.
For this engagement, however, the objective is to restore QR scanning in the current Cordova application so that it can be used for a pilot deployment.
We are looking for someone who is comfortable solving difficult legacy debugging problems, not someone who will immediately recommend replacing the entire application.
Should the developer determine that a reliable fix is not technically feasible, we expect a clear written explanation supported by diagnostic evidence. We value an honest technical assessment over unnecessary billable hours.
Please Do Not Apply If
Please do not apply if:
- You have no direct Cordova plugin-development or debugging experience.
- Your experience is limited to Flutter, React Native, or standard Ionic UI development.
- You intend to replace the application rather than diagnose the current implementation.
- You cannot use ADB logcat or investigate JavaScript-to-native bridge failures.
- You plan to submit a generic proposal without addressing the technical issue.
Proposal Requirements
Please include the following in your proposal:
- Your hourly rate or fixed-price estimate
- Your estimated diagnostic and implementation timeline
- A brief explanation of how you would begin investigating the issue
- Examples of relevant Cordova, Android camera, barcode, or QR-scanner work
- Any initial technical questions
- Your availability to begin
We are looking for an experienced specialist rather than the lowest-priced proposal.
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