Android Application class that is aware of if it is being created in the context of unit/instrumentation tests where the full application initialization is not desirable.

SampleApplication.java

package com.myapp;

public class SampleApplication extends TestingAwareApplication {
    @Override
    protected String getFullyQualifiedTestFile() {
        return "com.myapp.TestMode";
    }

    @Override
    protected void initAppInstance() {
        // Whatever you need to initialize...
    }
}

TestingAwareApplication.java

package com.myapp;

import android.app.Application;
import android.util.Log;

import com.myapp.BuildConfig;

public abstract class TestingAwareApplication extends Application {
    private static final String TAG = TestingAwareApplication.class.getSimpleName();

    private boolean initialized = false;

    @Override
    public void onCreate() {
        super.onCreate();

        if (isTestExecution()) {
            Log.e(TAG, "Starting without initializing the application for automated tests; call initAppInstanceIfNeeded() manually if needed.");
        } else {
            initAppInstanceIfNeeded();
        }
    }

    private boolean isTestExecution() {
        if (BuildConfig.DEBUG) {
            try {
                getClassLoader().loadClass(getFullyQualifiedTestFile());
                return true;
            } catch (Exception e) {
                return false;
            }
        }

        return false;
    }

    /**
     * Return something from the androidTest source set.
     * @return Example: "com.myapp.TestMode"
     */
    protected abstract String getFullyQualifiedTestFile();

    public void initAppInstanceIfNeeded() {
        if (!initialized) {
            initAppInstance();
            initialized = true;
        }
    }

    protected abstract void initAppInstance();
}

TestMode.java

package com.myapp;

/**
 * The main application class will try to load this class in via the classloader to determine if it
 * is being run in the context of automated tests or not.  It offers no other value to the test
 * suite beyond changing the initialization behavior of the main application class.
 * 
 * Ensure that this class lives in the androidTest source set!
 */
@SuppressWarnings("unused")
public class TestMode {

}