Proper example for using application context is not clear.

https://github.com/codepath/android_guides/wiki/Using-Context

* If storing in a private static variable is wrong, why is this fragment still seemingly using it?
* Why even use a singleton then?

``` java
public static CustomManager getInstance(Context context) {
if (sInstance == null) {
sInstance = new CustomManager(context.getApplicationContext());
}

return sInstance;
}
```