Isn't this called "upward" compatible?

Which language and IDE do you use?

Every Logcat message has an appid. Normally ADT plugin automatically filters the messages of your currently running app but it seems this isn't the case for you.

Please filter the messages first and don't pick a random message from the universal logcat log.

I do not think your problem is the sdk version.

targetSDKVersion of 21 already means you are using 5.0 behaviour, on devices with this version installed

minSDKVersion of 16 means it will also run on anything from 4.1.

Even though things change slightly between versions, the changes are not that big, it is mainly that new APIs are added, so it is unlikely your application needs lots of change to work.

But first of all, you need to find out what is actually going wrong.

The best way to do this is to run the application from within eclipse in debug mode. Then you can set breakpoints and step through your program line by line, and make sure variables have the values they are supposed to have, and that all objects you try to create is created properly.

If there is a crash, it will likely stop and show you where in your program go wrong, and what exceptions.

Then you have to figure out why from there.

The E/SMD error message you see most likely has nothing to do with your application. Unfortunately logcat is very polluted by system services puking uninteresting information. (On one device I used, just starting a sound generated more then 30000 lines of debug output. yes, thirty thousands. unbelievable...)

Eclipse is supposed to show filtered logcat messages, but this does not always work. If not, you can filter it out yourself from running the command line tool "logcat"

Personally I use grep on OSX to filter.. (logcat | grep <process id>)

That number in parenthesis on the line is the process id of the application that generate the message.

Check what process id your application has when it starts up, and then use that to see what messages your application is showing.

Indeed, as I also said. Filter it!

Picking a random message from the universal log doesn't help.

I have overseen that you wrote "Java" and only read "Android" which could also mean C++, I am sorry.

If you are using Java I supposed you know how an error message normally looks like:

07-02 13:38:26.990: E/AndroidRuntime(1905): FATAL EXCEPTION: GLThread 9899
07-02 13:38:26.990: E/AndroidRuntime(1905): java.lang.IndexOutOfBoundsException: Invalid index 0, size is 0
07-02 13:38:26.990: E/AndroidRuntime(1905):     at java.util.ArrayList.throwIndexOutOfBoundsException(ArrayList.java:255)
07-02 13:38:26.990: E/AndroidRuntime(1905):     at java.util.ArrayList.get(ArrayList.java:308)
07-02 13:38:26.990: E/AndroidRuntime(1905):     at com.google.liquidfun.look.LookDatabase.draw(LookDatabase.java:49)
07-02 13:38:26.990: E/AndroidRuntime(1905):     at com.google.liquidfun.look.Look.onDrawFrame(Look.java:181)
07-02 13:38:26.990: E/AndroidRuntime(1905):     at android.opengl.GLSurfaceView$GLThread.guardedRun(GLSurfaceView.java:1531)
07-02 13:38:26.990: E/AndroidRuntime(1905):     at android.opengl.GLSurfaceView$GLThread.run(GLSurfaceView.java:1248)
07-02 13:38:39.745: E/OpenGLRenderer(1905): SFEffectCache:clear(), mSize = 0

This is also the case for android. Without a real error message nobody can help you from those few information you provided.

Refer to @Olof Hedman to set up a filter correctly.

Mhm I see.

Rather use PID or your "Application Name" for the filter.

The ADT plugin normally uses automatically the Application Name.

The application name is the package your launcher activity is located in, you don't have to use the full package name if you are not sure.

So if your package is called "com.package.name.activitypackage" you can also just type "com.package" in the Application Name filter option.

Then start your application again.

Hope this helps :)

Best Regards