为什么我的Android应用程序不能与某些Android版本一起使用？

Question

我创建了我的应用程序。它可以在我的设备上正常运行，但是我注意到它不适用于某些android版本（Android 7.1.1）。我的库支持android 4.2及更高版本。我测试的设备是android 6.0。这可能是什么原因。如何为Android 4.2设置它？

我的爷爷：

apply plugin: 'com.android.application'

android {
compileSdkVersion 27
defaultConfig {
    lintOptions {
        abortOnError false
    }
    applicationId "test"
    minSdkVersion 16
    targetSdkVersion 27
    versionCode 1
    versionName "1.0"
    resConfigs "en"
    testInstrumentationRunner 
   "android.support.test.runner.AndroidJUnitRunner"
    multiDexEnabled true

}
buildTypes {
    release {
        shrinkResources false
        minifyEnabled false
        proguardFiles getDefaultProguardFile('proguard-android.txt'), 
  'proguard-rules.pro'
    }
}
}

dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
//noinspection GradleCompatible
implementation 'com.android.support:appcompat-v7:27.+'
implementation 'com.android.support:design:27.+'
implementation 'com.android.support.constraint:constraint-layout:1.1.1'
implementation 'com.google.firebase:firebase-database:16.0.1'
implementation 'com.android.support:cardview-v7:27.+'
implementation 'com.android.support:support-v4:27.+'

implementation 'com.google.firebase:firebase-messaging:17.1.0'
implementation 'com.google.firebase:firebase-core:16.0.1'

testImplementation 'junit:junit:4.12'
androidTestImplementation 'com.android.support.test:runner:1.0.2'
androidTestImplementation 'com.android.support.test.espresso:espresso- 
core:3.0.2'

implementation 'com.flaviofaria:kenburnsview:1.0.7'
implementation 'com.squareup.picasso:picasso:2.71828'

implementation "com.andkulikov:transitionseverywhere:1.7.9"

implementation 'com.baoyz.pullrefreshlayout:library:1.2.0'

implementation 'com.github.Hitomis:CircleMenu:v1.1.0'

implementation 'com.google.android.gms:play-services-ads:15.0.0'
}

apply plugin: 'com.google.gms.google-services'