Handling different versions of Android
Most of the time throughout this book, we haven't paid any attention to supporting older Android devices, the main reason being that all the up-to-date parts of the API we have been using work on such a high percentage of devices (in excess of 99%) that it has not seemed worthwhile. Unless you intend on carving out a niche in apps for ancient Android relics, this seems like a sensible approach. Regarding playing sounds, however, there have been some relatively recent modifications to the Android API.
Actually, this isn't immediately a big deal because devices newer than this can still use the old parts of the API. But it is good practice to specifically handle these differences in compatibility, because eventually, one day, the older parts might not work on newer versions of Android.
The main reason for discussing this here and now is that the slight differences in pre- and post-Android Lollipop sound handling give us a good excuse...
