[ DPS 2015 ] APP on Android 4.1.1

Hello

My APP's don't install in Android 4.1.1.

Work's fine in Android 4.4.2.

I´m using DROPBOX to install the application in the  development version.

Using USB cable and a file manager application results in the same problem.

The download process works fine. In the android 4.1.1, in the installation process a message says: "There was a problem parsing the package."

Thanks for any information.

Leo