diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index 96204e70..fecc6bdc 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -13,6 +13,24 @@ jobs:
     - name: Fetch submodules
       run: git submodule init && git submodule update
 
+    - name: Cache Gradle packages
+      uses: actions/cache@v3
+      with:
+        path: |
+          ~/.gradle/caches
+          ~/.gradle/wrapper
+        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+        restore-keys: |
+          ${{ runner.os }}-gradle-
+
+    - name: Cache NuGet packages
+      uses: actions/cache@v3
+      with:
+        path: ~/.nuget/packages
+        key: ${{ runner.os }}-nuget-${{ hashFiles('src/**/*.csproj', 'src/**/packages.config') }}
+        restore-keys: |
+          ${{ runner.os }}-nuget-
+
     # As per https://github.com/actions/runner-images/blob/main/images/macos/macos-12-Readme.md#visual-studio-for-mac
     - name: Switch to Visual Studio 2019
       if: ${{ false }} # Not needed. We stay with the default 'Visual Studio 2022' of macos-12 runner.
@@ -107,12 +125,52 @@ jobs:
 
     runs-on: ubuntu-22.04
 
+    env:
+        # Build Artifact of xamarin.android-oss dated 2021-02-02, master branch (= version 11.2.99) - *.deb cannot be installed because "lxd" package is not anymore shipped in current ubuntu version
+        #xamarin_url: https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzM0NTE3L2FydGlmYWN0TmFtZS9JbnN0YWxsZXJzKy0rTGludXg1/content?format=zip
+
+        # Build Artifact of xamarin.android-oss dated 2021-03-23, d16-9 branch (= version 11.2.2) - *.deb cannot be installed because "lxd" package is not anymore shipped in current ubuntu version
+        #xamarin_url: https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzM3Njg0L2FydGlmYWN0TmFtZS9JbnN0YWxsZXJzKy0rTGludXg1/content?format=zip
+
+        # Build Artifact of xamarin.android-oss dated 2021-07-21, master branch (= version 11.4.99)
+        xamarin_url: https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzQzNjU5L2FydGlmYWN0TmFtZS9pbnN0YWxsZXJzLXVuc2lnbmVkKy0rTGludXg1/content?format=zip
+
+        # Build Artifact of xamarin.android-oss dated 2022-02-16, master branch (= version 12.2.99) - Build fails with this version as of 2022-12-02 because there is some issue with SamsungPass. Removing SamsungPass would make the build succeed.
+        #xamarin_url: https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzU0OTUzL2FydGlmYWN0TmFtZS9pbnN0YWxsZXJzLXVuc2lnbmVkKy0rTGludXg1/content?format=zip
+
     steps:
     - uses: actions/checkout@v3
 
     - name: Fetch submodules
       run: git submodule init && git submodule update
 
+    - name: Cache Gradle packages
+      uses: actions/cache@v3
+      with:
+        path: |
+          ~/.gradle/caches
+          ~/.gradle/wrapper
+        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+        restore-keys: |
+          ${{ runner.os }}-gradle-
+
+    - name: Cache NuGet packages
+      uses: actions/cache@v3
+      with:
+        path: ~/.nuget/packages
+        key: ${{ runner.os }}-nuget-${{ hashFiles('src/**/*.csproj', 'src/**/packages.config') }}
+        restore-keys: |
+          ${{ runner.os }}-nuget-
+
+    - name: Cache Xamarin.Android packages
+      id: xamarin_cache
+      uses: actions/cache@v3
+      with:
+        path: ~/xamarin.android-oss
+        key: ${{ runner.os }}-xamarin.android-oss-${{ env.xamarin_url }}
+        restore-keys: |
+          ${{ runner.os }}-xamarin.android-oss-${{ env.xamarin_url }}
+
     - name: Install Mono
       if: ${{ false }}  # disable for now since it is already installed on the runner which uses the same repo https://github.com/actions/runner-images/blob/main/images/linux/Ubuntu2204-Readme.md#language-and-runtime
       run: |
@@ -122,29 +180,22 @@ jobs:
         sudo apt update &&
         sudo apt-get -y -t stable-focal install mono-complete
 
-    - name: Install Xamarin.Android
+    - name: Download & unpack Xamarin.Android
+      if: steps.xamarin_cache.outputs.cache-hit != 'true'
       run: |
         set -x
-        cd $HOME
-
-        # Build Artifact of xamarin.android-oss dated 2021-02-02, master branch (= version 11.2.99) - *.deb cannot be installed because "lxd" package is not anymore shipped in current ubuntu version
-        #wget -O "installers-unsigned - Linux.zip" https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzM0NTE3L2FydGlmYWN0TmFtZS9JbnN0YWxsZXJzKy0rTGludXg1/content?format=zip &&
-
-        # Build Artifact of xamarin.android-oss dated 2021-03-23, d16-9 branch (= version 11.2.2) - *.deb cannot be installed because "lxd" package is not anymore shipped in current ubuntu version
-        #wget -O "installers-unsigned - Linux.zip" https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzM3Njg0L2FydGlmYWN0TmFtZS9JbnN0YWxsZXJzKy0rTGludXg1/content?format=zip &&
-
-        # Build Artifact of xamarin.android-oss dated 2021-07-21, master branch (= version 11.4.99)
-        wget -O "installers-unsigned - Linux.zip" https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzQzNjU5L2FydGlmYWN0TmFtZS9pbnN0YWxsZXJzLXVuc2lnbmVkKy0rTGludXg1/content?format=zip &&
-
-        # Build Artifact of xamarin.android-oss dated 2022-02-16, master branch (= version 12.2.99) - Build fails with this version as of 2022-12-02 because there is some issue with SamsungPass. Removing SamsungPass would make the build succeed.
-        #wget -O "installers-unsigned - Linux.zip" https://artprodcus3.artifacts.visualstudio.com/Ad0adf05a-e7d7-4b65-96fe-3f3884d42038/6fd3d886-57a5-4e31-8db7-52a1b47c07a8/_apis/artifact/cGlwZWxpbmVhcnRpZmFjdDovL3hhbWFyaW4vcHJvamVjdElkLzZmZDNkODg2LTU3YTUtNGUzMS04ZGI3LTUyYTFiNDdjMDdhOC9idWlsZElkLzU0OTUzL2FydGlmYWN0TmFtZS9pbnN0YWxsZXJzLXVuc2lnbmVkKy0rTGludXg1/content?format=zip &&
-
+        cd $HOME &&
+        wget -O "installers-unsigned - Linux.zip" ${{ env.xamarin_url }} &&
         unzip "installers-unsigned - Linux.zip" &&
         mkdir -p xamarin.android-oss &&
         DIR=$(unzip -Z -1 installers-unsigned\ -\ Linux.zip   | cut -d '/' -f1 | sort -u) &&
         tar -xvf "$DIR"/xamarin.android-oss-*.tar.* --strip-components=1 -C xamarin.android-oss &&
-        sudo apt install -y ./"$DIR"/*.deb
+        mv "$DIR"/*.deb xamarin.android-oss
 
+    - name: Setup Xamarin.Android
+      run: |
+        cd $HOME &&
+        sudo apt install -y ./xamarin.android-oss/*.deb &&
         echo "$HOME/xamarin.android-oss/bin/Release/bin" >> $GITHUB_PATH
 
     - name: Switch to JDK-8
@@ -237,6 +288,24 @@ jobs:
     steps:
     - uses: actions/checkout@v3
 
+    - name: Cache Gradle packages
+      uses: actions/cache@v3
+      with:
+        path: |
+          ~/.gradle/caches
+          ~/.gradle/wrapper
+        key: ${{ runner.os }}-gradle-${{ hashFiles('**/*.gradle*', '**/gradle-wrapper.properties') }}
+        restore-keys: |
+          ${{ runner.os }}-gradle-
+
+    - name: Cache NuGet packages
+      uses: actions/cache@v3
+      with:
+        path: ~/.nuget/packages
+        key: ${{ runner.os }}-nuget-${{ hashFiles('src/**/*.csproj', 'src/**/packages.config') }}
+        restore-keys: |
+          ${{ runner.os }}-nuget-
+
     - name: Fetch submodules
       run: git submodule init && git submodule update
 
@@ -308,3 +377,20 @@ jobs:
 
     - name: Perform "make distclean"
       run: make distclean
+
+    # Stop gradle daemon so as to be able to save the Gradle cache
+    # Otherwise, error is: tar.exe: Couldn't open C:/Users/runneradmin/.gradle/caches/transforms-2/transforms-2.lock: Permission denied
+    - name: Stop gradle daemon
+      shell: cmd
+      run: |
+        echo on
+        call src\java\JavaFileStorageTest-AS\gradlew.bat --stop
+        echo on
+        call src\java\KP2ASoftkeyboard_AS\gradlew.bat --stop
+        echo on
+        call src\java\Keepass2AndroidPluginSDK2\gradlew.bat --stop
+        echo on
+        call src\java\KP2AKdbLibrary\gradlew.bat --stop
+        echo on
+        call src\java\PluginQR\gradlew.bat --stop
+        echo on