* Don't target SDKs above 27.1.1
* If your app is all correct, but crashes immediately when opened, open build.gradle and add:
implementation ('android.arch.core:runtime:1.1.1') {
force = true
}
in your dependencies, so it flows like:
dependencies {
implementation fileTree(dir: 'libs', include: ['*.jar'])
implementation ('android.arch.core:runtime:1.1.1') {
force = true
}
implementation 'com.android.support:appcompat-v7:27+'
}