What does "Failure [INSTALL_FAILED_OLDER_SDK]" mean in Android Studio?

Question

I got this Froyo (2.2) device that I am using to make an app. When I try to run the app directly to the device it shows an error saying

pkg: /data/local/tmp/com.example.HelloWorldProject Failure [INSTALL_FAILED_OLDER_SDK] 

and in another window there's an error saying

Unable to attach test reporter to test framework or test framework quit unexpectedly 

What seem to make the said errors?

EDIT:

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?> <manifest xmlns:android="http://schemas.android.com/apk/res/android"           package="com.test.helloworld"           android:versionCode="1"           android:versionName="1.0">      <uses-sdk             android:minSdkVersion="8"             android:targetSdkVersion="17"/>      <application             android:allowBackup="true"             android:debuggable="true"             android:icon="@drawable/ic_launcher"             android:label="@string/app_name"             >         <activity                 android:name="com.example.HelloWorldProject.MyActivity"                 android:label="@string/app_name">             <intent-filter>                 <action android:name="android.intent.action.MAIN"/>                  <category android:name="android.intent.category.LAUNCHER"/>             </intent-filter>         </activity>     </application>  </manifest> 

Answer 1

After I changed

defaultConfig {     applicationId "com.example.bocheng.myapplication"     minSdkVersion 15     targetSdkVersion 'L' #change this to 19     versionCode 1     versionName "1.0" } 

in build.gradle file.

it works