Are these dark revolving progress dialogs in Amazon and Engadget apps standard on Android?
This is a ProgressDialog, with setIndeterminate (true).
From http://developer.android.com/guide/topics/ui/dialogs.html#ProgressDialog
ProgressDialog dialog = ProgressDialog.show(MyActivity.this, "", "Loading. Please wait...", true);
The indefinite progress bar does not actually show the panel; it shows circular activity. I'm sure you know what I mean :)
Today the situation has changed a bit.
Now we avoid using the ProgressDialog to display rotation speed:
If you want to turn the application on, you should use activity indicators:
http://developer.android.com/design/building-blocks/progress.html#activity