Determine a suitable default value for minSdkVersion

The minSdkVersion is currently set to 17 (Android-4 2012).

When building the app with a common plugin like @nativescript/background-http the build will fail.

Execution failed for task ':app:processDebugMainManifest'.
Manifest merger failed : uses-sdk:minSdkVersion 17 cannot be smaller than version 21 declared in library [net.gotev:uploadservice:4.7.0] /Users/ianbrindley/.gradle/caches/transforms-3/24fa1312ea1be6efbab27240facdcfb1/transformed/jetified-uploadservice-4.7.0/AndroidManifest.xml as the library might be using APIs not available in 17
        Suggestion: use a compatible library with a minSdk of at most 17,
                or increase this project's minSdk version to at least 21,
                or use tools:overrideLibrary="net.gotev.uploadservice" to force usage (may lead to runtime failures)

Instead I have to add additional configuration to gradle to get this plugin to work.

I suggest that the minSdkVersion is set to 21.

デフォルトの minSdkVersion を定義している Android のビルド設定から始め、@nativescript/background-http で manifest-merger の失敗を再現します。デフォルトを 17 から 21 に変更することによる互換性への影響を確認し、その後、追加の Gradle 設定なしでプラグインをビルドできることを検証します。プロジェクトが合意したデフォルトを使用し、報告されたビルドが成功すれば完了です。