PIN number is NOT needed for Oudie Live.
If you see a screen on your smartphone asking you to enter the PIN number this points to a bug in Android which is corrected in Android 4.3 and later versions. All earlier versions of Android will not be reliable in connecting to the Smartphone because of this bug unfrotunately.
The good news is that Oudie Live on Android 4.3 and later works for days and weeks without a problem and without you having to do anything to it. If you are a frequent flyer we recommend that you always keep the Oudie Live application running in the background and it will do its magic without any interaction from your side. This works particularly well with phones running Bluetooth 40 Low Energy where it is not possible to see a drop in the battery consumption because of the inactive app running in the bacground.