The Android 2.2 application APK file which is unsigned to install in Android 2.1 HTC hero phone for testing

I copied the .apk file to phone and trying to install through Astro file manager but it is not showing Install button, so I am not able to install. The htc hero phone android ver 2.1 and my apk is build in Android 2.2. Through adb install to install the apk also showing Failure [INSTALL开发者_Go百科_FAILED_OLDER_SDK], so please help me out, how to install my apk in my android HTC hero mobile to test my APK>

If your application has a minimum SDK version of 2.2, it won't work on your HTC Hero with version 2.1. Set your application's min SDK version to 2.1 using this tag in your Manifest:

<uses-sdk android:minSdkVersion="4" />

However, this won't work if your application uses features available in Android 2.2 and higher, so if it's true, then you won't be able to run your app on HTC Hero. Hope this helps.

U can install Android 2.1(API level 7) application on Andriod 2.2(API level 8) device but cant install 2.2 app on 2.1 device everytime. If u have source code then add below tag in ur manifest The application will get installed. Application may not work if its using API introdused in 2.2 and not available in 2.1.