Fixes #228
You must renmove the callback listeners attached with the service when you
destroy the activities.
<TextView xmlns:android="http://schemas.android.com/apk/res/android"
android:textColor="@color/white" android:textColorHighlight="@color/red"
android:textSize="18sp" android:typeface="normal" android:textStyle="bold"
android:id="@+id/contactlist_group"></TextView>