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Brand TruID client

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Last updated: Jan 30, 2024 by Josefin Klang (Deactivated)
2 min read

This article describes how to brand a TruID client that shall be used with Smart ID Digital Access component.

TruID is a client application that generates One-Time Passwords (OTP). There is one generic TruID client and one TruID client for Android.

  • In the generic TruID client both text and graphics can be branded. The generic TruID client is located on the distribution disks under <DISK>/Client/Java/TruID.jar. This file is a ZIP file containg code, graphics and texts for the client. 

  • In the TruID for Android client only the graphics can be branded. The application is an apk file that is packed using the zip format. 

Step-by-step instructions

  1. Unpack the zip-file in the images directory.

  2. To update the icon used for the application, update icon.png.

  3. To update the logotype, update the files 0.png (the largest logotype), 1.png (the second largest logotype) and so on.

  4. To update the black-and-white logotypes, update the files in the images/mono directory in the same way.

Note: When changing any files in the zip archive, the corresponding JAD file has to be updated with the new file size of the JAR file.



  1. Find the locale for the client in the locale directory.

  2. Use the file en.properties as a template for other locale files (en.properties is for English, this is the default).

  3. If Swedish shall be used, create a file called sv.properties in the locale directory. When the application is started, the application will use the Swedish locale for showing all texts.

The client reports the current locale when opening the “about” page in the client. For example, if the phone’s locale is set to Swedish, the about page will report “sv” as language.



  1. Acquire the application and unzip the contents.

  2. Modify any of these images in the res/drawable directory:

After the graphics has been updated a new application has to be created. These are the tools used to create the new application:

  • keytool, jarsigner and zipalign (3:rd party tools).

    • keytool and jarsigner comes from the JDK.

    • zipalign comes from the Android SDK. Download and install SDK according to its documentation to use zipalign.

  1. Remove the old signature by removing the META-INF directory.

  2. Pack up the application:

    1. Zip up all the files into a zip file with the modified graphics.

    2. Rename the zip file to TruID-unaligned.apk.

  3. Sign the application. All Android applications must be signed.

    1. Generate key to be used for signing. It is important that the signature keys are safely stored.

      keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -validity 10000

    2. Sign the .apk file

      jarsigner -verbose -keystore my-release-key.keystore TruID-unaligned.apk alias_name

  4. Align the signed apk.

    zipalign -v 4 TruID-unaligned.apk TruID.apk

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