Q:

Entering app exactly as it was left

I know there must be douzens of answers to this question out there, but either i cant't find them or I don't understand them.
The Question:
How do I get my app to exactly start as it was left?
F.e. dynamicly added checkBoxes shouldn't dissapear!

A:

There is no "out of the box" way of doing it. You could save the current state of your Activity in some way (More on persistence)
Then you need to be able to rebuild the desired state of the persisted state in your Activity lifecycle
You could save and load with the shared preferences for example:
public void saveState(YourState state) {
    SharedPreferences sharedPreferences = app.getSharedPreferences(R.string.preference_file_key, Context.MODE_PRIVATE)
    sharedPreferences.edit()
        .putString("CustomAtt", state.getCustomAtt())
}

public YourState loadState() {
    SharedPreferences sharedPreferences = app.getSharedPreferences(R.string.preference_file_key, Context.MODE_PRIVATE)
    String customAtt = sharedPreferences.getString("CustomAtt", "DefaultValue")
    return new YoutState(customAtt)
}

And use it like this
@Override
protected void onCreate(Bundle savedInstanceState) {
    YourState state = loadState();
    // Rebuild your activity based on state
    someView.setText(state.getCustomAtt())
}

