`android-sdk-min` is 28

[dfabulich]

The generated settings.gradle.kts file in the .build folder has this line:

version("android-sdk-min", "28")

(EDIT: Previously it was 29.)

That's kinda high. According to the Android Studio "Help me choose" dialog, supporting API level 28 and higher only supports 95.3% of users as of December 1, 2025.

When creating a new project as of today, Android Studio recommends supporting at least back to API 24.

[dfabulich]

If I manually override this in Android/app/build.gradle.kts, will that break anything?

[marcprux]

TBH, I don't recall where the 29 min SDK level came from. I just tried bumping it down to 26 with the Hello Skip sample, and it works fine. Any lower, and we get an error about the <adaptive-icon> element in the AndroidManifest.xml, but if that was stripped out, you might be able to bring it even lower.

Some of Skip's features, like dark mode synchronization with the system default setting, will only work in API 29 or higher. But these shouldn't prevent your app from running.

I recommend trying to bump it down and experimenting on an emulator with an older minimum API and see if it works OK.

[marcprux]

P.S. SkipFuse (i.e., non-transpiled native Swift on Android) does require API 28 or higher, because that is the minimum version that the official Swift Android SDK will support. This doesn't affect SkipLite transpiled apps, only SkipFuse.

[dfabulich]

For the record, the way to set minSdk in a Skip Lite project is with these settings in skip.yml:

settings:
  contents:
    - block: 'dependencyResolutionManagement'
      contents:
        - block: 'versionCatalogs'
          contents:
            - block: 'create("libs")'
              remove: ['version("android-sdk-min", "28")']
              contents:
                - 'version("android-sdk-min", "26")'

This is a bit fragile, because it requires explicitly removing the existing version("android-sdk-min", "28") line. (It's not enough to add our own "26" line, because our addition will appear last; the default "28" line will override it.)

Also, I was able to use API level "24" in https://github.com/skiptools/skipapp-hello/ by moving app/src/main/res/mipmap-anydpi/ic_launcher.xml to app/src/main/res/mipmap-anydpi-v26/ic_launcher.xml. This ensures that API 24 and API 25 will use the legacy ic_launcher.png files, e.g. app/src/main/res/mipmap-xxxhdpi/ic_launcher.png, and API 26+ will use the adaptive icon.

[marcprux]

I've always wondered why this didn't work. So earlier settings override later ones? I would have assumed the opposite. This is also probably why it isn't possible to override the versions for various libraries (like compose) at the app level.

Maybe we could add some special-case logic for the settings/libs section where we just output them all in reverse order…

[dfabulich]

Just a note here… I foolishly shipped with minSdk 24 without adequate testing. (I was testing on Android 8 when I thought I was testing on Android 7!)

I figured I'd make some notes here about what went wrong, in case someone else tries to walk a similar path.

1. Desugaring. Skip uses a bunch of Java 8+ APIs that are available natively in Android 8 but not available in Android 7. You have to enable desugaring to fix them. https://developer.android.com/studio/write/java8-support-table https://developer.android.com/studio/write/java11-nio-support-table I've got an example in Support Android 7 (API level 24) skipapp-showcase#108
   • Do it in Android/app/build.gradle.kts, not in skip.yml
   • Be sure to use desugar_jdk_libs_nio so you get File NIO support. desugar_jdk_libs is not enough.
2. You might need to use SkipSQLPlus on Android 7. Android 7 ships SQL 3.9.2 (2015). Android 8 ships 3.18.2 (2017).

I've also filed some backwards-compatibility PRs.

• Use ResourcesCompat.getFont() for backwards compatibility with API 24 skip-ui#445
• Use BitmapFactory on old versions of Android skip-ui#446
• Android 7 backport skip-sql#29

Testing tips:

• On Apple Silicon, there's no Google Play Store image for Android 7 or Android 8. Use a "Google APIs" image instead.

• Android 7 and Android 8 ship with ancient versions of WebView, which are meant to be autoupgraded by Google Play Store. That's not going to work on these Google APIs images. If you want to upgrade the WebView, you'll have to run the emulator with -writeable-system, then download a WebView APK from APKMirror, and install it like this:

  adb root
  adb remount
  
  adb push com.google.android.webview_117.0.5938.60-593806001_minAPI24_maxAPI28\(arm64-v8a,armeabi-v7a\)\(nodpi\)_apkmirror.com.apk /system/app/WebViewGoogle/WebViewGoogle.apk
  adb shell chmod 644 /system/app/WebViewGoogle/WebViewGoogle.apk
  
  adb reboot
  

  This change won't stick. When you stop the emulator and rerun it, it will launch from its original system image, reverting your WebView.

• And you'll probably need to install new TLS certificates.

  CERT_TMP="$(mktemp)"
  trap 'rm -f "${CERT_TMP}"' EXIT
  
  curl -sS -o "${CERT_TMP}" https://letsencrypt.org/certs/isrgrootx1.pem
  
  HASH="$(openssl x509 -inform PEM -subject_hash_old -in "${CERT_TMP}" | head -1)"
  CERT_DEST="${HASH}.0"
  
  adb root
  adb remount
  
  adb push "${CERT_TMP}" "/system/etc/security/cacerts/${CERT_DEST}"
  adb shell chmod 644 "/system/etc/security/cacerts/${CERT_DEST}"
  adb shell chcon u:object_r:system_file:s0 "/system/etc/security/cacerts/${CERT_DEST}"
  
  adb reboot
  

• The Android 7 emulator sets dalvik.vm.heapgrowthlimit to 48m, which is very tight. You might need to set android:largeHeap="true" on your AndroidManifest.xml <application> element to avoid OutOfMemoryError issues on Android 7.