Android APIs
package

android.support.v4.os

Support android.os classes to assist with development of applications for android API level 4 or later.

Interfaces

CancellationSignal.OnCancelListener Listens for cancellation. 
ParcelableCompatCreatorCallbacks<T> Callbacks a Parcelable creator should implement. 

Classes

AsyncTaskCompat Helper for accessing features in AsyncTask introduced after API level 4 in a backwards compatible fashion. 
CancellationSignal Static library support version of the framework's CancellationSignal
EnvironmentCompat Helper for accessing features in Environment introduced after API level 4 in a backwards compatible fashion. 
ParcelableCompat Helper for accessing features in Parcelable introduced after API level 4 in a backwards compatible fashion. 
TraceCompat Writes trace events to the system trace buffer. 

Exceptions

OperationCanceledException An exception type that is thrown when an operation in progress is canceled.