HEADS UP: For those publishing the app on the Apple App Store or via a Mobile Device Management (MDM) system, please note that in order to be able to re-sign and then publish your app, you need to download and execute the new version of the resign.sh script. This file is also attached to the Re-signing the .ipa chapter below in this article.

Important note: you won’t be able to publish your branded app if you don’t re-sign your app using the new version of the resign.sh file.

Introduction

In your learning platform, you can create a branded mobile app for your users’ on-the-go learning. In this way, your learners can do their training on a mobile app branded for your company.

Refer to this article to learn how to create and configure your branded app, generate the build and then download the package in order to publish your custom version of the Go.Learn mobile app on the app stores. To know technical requirements and information needed to create your own branded app, refer to this article.

If you publish your app on iOS App Store, you are required to submit the Export Compliance and the Self-Classification Report for Encryption Items in order to be compliant with the U.S. Encryption and Export Administration Regulations (EAR). To know how to produce and present this report, refer to this article.

This article outlines how to re-sign and then publish your branded mobile app. Once you’ve created your branded app, in order to publish it on the application store (Google Play for Android and App Store for iOS) you have to replace the digital signature temporarily applied by Docebo with your own signature generated in-house (for Android) or with the signing certificate assigned by the App Store (for iOS).

If you don’t apply the new signature, the package can’t be uploaded on the application store. Refer to the following sections for more information about the re-signing process for Android and for iOS.

Please note that Branded Mobile App Publisher is a very technical functionality. We suggest contacting a member of your company’s IT department to perform the configuration properly.

Also note that Docebo is not responsible for the content of external documents written by other companies (i.e. Apple, etc.). Remember that it is your responsibility to check if these documents are updated or changed in any way.

Android Google Play Store

The re-signing process for the Android Google Play Store is composed of two steps. You must first create a keystore if you don’t have one yet. If you already published an Android app, you can use the same keystore. Then, you need to re-sign the Android Package (APK) or the Android App Bundle (AAB), according to the package format you chose when configuring the app technical details in the Settings section of the Android app tab.

Creating a Keystore

Begin by creating a keystore using the Java Keytool utility that comes with any standard JDK distribution and can be located at %JAVA_HOME%\bin. On Windows, this is usually C:\Program Files\Java\jre8\bin., while you don't need to care about the path on Mac OS.

On Windows, open a command prompt and switch to that directory. On a Mac, just open a terminal. Then, enter a command like this one:

keytool -genkey -v -keystore my-release-key.keystore -alias alias_name -keyalg RSA -keysize 2048 -validity 10000

The Keytool prompts you to provide passwords for the keystore, then you will be asked to provide the Distinguished Name fields: Finally, type the password for your key (if required). The keystore is now generated as a file called my-release-key.keystore saved in the directory in which you’re currently located. The keystore and the key are protected by the passwords that you entered. The keystore contains a single key, which is valid for 10,000 days (as given in the -validity parameter). The alias is the name that you will use later to refer to this keystore when signing your application.

Please note: Save the keystore and the password for later uses, because you’ll have to use them anytime you need to publish an update.

To learn more about Keytool, you can refer to this Oracle document. You can also find a detailed document about this topic on Stack Overflow.

Re-signing the .aab or the .apk

In order to reassign a signature to an AAB or to an APK, you have to delete the META-INF from your AAB or your APK and then sign it again. Remember that you shouldn't extract the files; you just need to remove the entry from the archive.

You can do it in many ways, but the fastest way is using the system shell. Let’s assume that you have a MyApp.aab file (or a MyApp.apk file) and a keystore called ‘my-release-key.keystore’, the alias is ‘alias_name‘, the keystore’s password is ’secret’ and the key’s password is ‘password123‘. If you don’t have a keystore, refer to the Creating a Keystore section above for further information on how to create it. Follow these steps to re-sign the .aab or the .apk file:

1. Remove the META-INF directory from the archive (both for Windows and Mac):

zip -d MyApp.aab META-INF/\* or zip -d MyApp.apk META-INF/\* 

2. Realign the app in order to be compliant with the Play Store tech requirements. The purpose is to ensure that all uncompressed data starts with a particular alignment relative to the start of the file (please note: follow this step for .apk files only)

For Windows:

zipalign -f -v 4 MyApp.apk MyAppAligned.apk

For Mac:

/Users/{YOUR_USER_NAME}/Library/Android/sdk/build-tools/{SDK_VER}/zipalign -f -v 4 ./MyApp.apk MyAppAligned.apk

3. Sign it again:

For Windows:

• AAB

jarsigner -verbose -sigalg SHA256withRSA -digestalg SHA-256 -keystore ./my-release-key.keystore ./MyAppSigned.aab alias_name

• APK

apksigner sign -v --out ./MyAppSigned.apk --ks ./my-release-key.keystore --ks-key-alias alias_name ./MyAppAligned.apk

For Mac:

• AAB

jarsigner -verbose -sigalg SHA256withRSA -digestalg SHA-256 -keystore ./my-release-key.keystore ./MyAppSigned.aab alias_name

• APK

/Users/{YOUR_USER_NAME}/Library/Android/sdk/build-tools/{SDK_VER}/apksigner sign -v --out ./MyAppSigned.apk --ks ./my-release-key.keystore --ks-key-alias alias_name ./MyAppAligned.apk

There is no security risk from the shell history because the passwords for your keystore and key are asked on the console. You are now ready to upload this .aab to the Android Google Play Store or to distribute the .apk.

Publishing

• More information about how to upload an app (from Google Play Console Help)
• When you update your app creating a new app version for the Android Google Play Store (but also when you create your app for the first time), you need to follow these guidelines to complete the form in Google Play Console on the types of data collected in your app. Note that the guidelines refer to the Go.Learn app configuration — please check each section, as your app may differ from Go.Learn (e.g. if you didn’t connect your app to Firebase, do not fill in the info on analytics; if you don’t have the Discover, Coach & Share module, fill in the module accordingly). If you don’t submit the form, you will see a warning message in the Messages Area of your Google Play Developer Console. 

Apple App Store

Prerequisites

In order to perform the re-signing process for the Apple App Store, you need:

Re-signing the .ipa

In order to re-sign the iOS .ipa package, a series of tools that are only available on Mac OS X are necessary, therefore you can’t re-sign an iOS app using a Windows PC. An .ipa is a zip file. In order to modify it, you have to extract it, sign it again and re-compress it.

Follow these steps to re-sign the .ipa file:

1. Move MyApp.ipa to a folder of your choice

2. Create and download the new Provisioning profile embedded.mobileprovision from the Apple Developer Console and save it into the .ipa folder (see point above). Follow the steps provided in this article from Apple KB.

3. The running security find-identity will give you a list of identities, from which you can choose the one you want (you have to search for the one starting with "iPhone Distribution"):

security find-identity -v -p codesigning

The result will be like the following:

1. 7D2A35B002F0577B66689713044BF66B4EEAC70F "iPhone Developer: Donald Duck (4J2CJZQ799)

2. C45CFD22CCC7BD2E84ED43D07719D709BC901322 "iPhone Distribution: A.C.M.E. (8YX56B3FLL)

4. Move the resign.sh script to the same folder and execute it (execute the script without args to have more info):

$./resign.sh  ./MyApp.ipa ./embedded.mobileprovision  “iPhone Distribution: A.C.M.E. (8YX56B3FLL)"

Please note: in case you receive the permission denied error shown in the image below, execute the following command: chmod 777 ./resign.sh After that, you can execute the resign.sh script without receiving any permission denied errors anymore. This .ipa is now signed with your new profile and you are now ready to upload this .ipa to Apple App Store using the application called Transporter (you can find it in your Application folder). If you don't have Transporter yet, you can install it from your Mac App Store. Refer to these articles (How to re-sign iOS builds, Inside Code Signing and Application Code Signing) to learn more about how to reassign a signature to an Apple .ipa file.

Publishing

You also need the following metadata to finish setting up the app in iTunesConnect:

App Specific Info

Version Specific Info

Refer to the following articles for more details about screenshot requirements and optional preview requirements, and read this article for further information.

Important Notes on the Publishing Process 

• When you update your app creating a new app version for the Apple App Store (but also when you create your app for the first time), you need to follow these guidelines to complete the form on the types of data collected in your app. Note that the guidelines refer to the Go.Learn app configuration — please check each section, as your app may differ from Go.Learn (e.g. if you didn’t connect your app to Firebase, do not fill in info on analytics).
• When uploading your branded app to Apple App Store, if you use custom SSO (Single Sign On), Apple may require an explanation about the reason why you use a non-standard login process.
• When publishing your branded mobile application to Apple App Store, you may be asked some questions about paid content and services. In this document you can find the answers applicable to the branded app you created with Docebo’s Branded Mobile App Publisher functionality (refer to the first section of the document if you use Docebo’s E-Commerce app to sell courses online through your platform creating your own marketplace, refer to the second section if you don’t use it). Once you reply to these questions, you can proceed with the publishing process.