| AbstractInputMethodService | AbstractInputMethodService provides a abstract base class for input methods. | 
                  
                    | AccessibilityService | Accessibility services should only be used to assist users with disabilities in using Android devices and apps. | 
                  
                    | AccountAuthenticatorActivity | Base class for implementing an Activity that is used to help implement an AbstractAccountAuthenticator. | 
                  
                    | Activity | An activity is a single, focused thing that the user can do. | 
                  
                    | ActivityGroup | A screen that contains and runs multiple embedded activities. | 
                  
                    | AliasActivity | Stub activity that launches another activity (and then finishes itself) based on information in its component's manifest meta-data. | 
                  
                    | AppFunctionService | Abstract base class to provide app functions to the system. | 
                  
                    | Application | Base class for maintaining global application state. | 
                  
                    | AutofillService | An AutofillServiceis a service used to automatically fill the contents of the screen on behalf of a given user - for more information about autofill, read Autofill Framework. | 
                  
                    | CallRedirectionService | This service can be implemented to interact between Telecom and its implementor for making outgoing call with optional redirection/cancellation purposes. | 
                  
                    | CallScreeningService | This service can be implemented by the default dialer (see TelecomManager.getDefaultDialerPackage()) or a third party app to allow or disallow incoming calls before they are shown to a user. | 
                  
                    | CameraPrewarmService | Extend this class to implement a camera prewarm service. | 
                  
                    | CarrierMessagingClientService | If the default SMS app has a service that extends this class, the system always tries to bind it so that the process is always running, which allows the app to have a persistent connection to the server. | 
                  
                    | CarrierMessagingService | A service that receives calls from the system when new SMS and MMS are sent or received. | 
                  
                    | CarrierService | A service that exposes carrier-specific functionality to the system. | 
                  
                    | ChooserTargetService | A service that receives calls from the system when the user is asked to choose a target for an intent explicitly by another app. | 
                  
                    | CloudMediaProvider | Base class for a cloud media provider. | 
                  
                    | CompanionDeviceService | A service that receives calls from the system with device events. | 
                  
                    | ConditionProviderService | A service that provides conditions about boolean state. | 
                  
                    | ConnectionService | An abstract service that should be implemented by any apps which either: 
                          
                          Once implemented, the  needs to take the following steps so that Telecom will bind to it:Can make phone calls (VoIP or otherwise) and want those calls to be integrated into the built-in phone app. Referred to as a system managed ConnectionService.Are a standalone calling app and don't want their calls to be integrated into the built-in phone app. Referred to as a self managed ConnectionService. | 
                  
                    | ContentProvider | Content providers are one of the primary building blocks of Android applications, providing content to applications. | 
                  
                    | ControlsProviderService | Service implementation allowing applications to contribute controls to the System UI. | 
                  
                    | CredentialProviderService | Service to be extended by credential providers, in order to return user credentials to the framework. | 
                  
                    | DeviceAdminService | Base class for a service that device owner/profile owners can optionally have. | 
                  
                    | DialogFragment | A fragment that displays a dialog window, floating on top of its activity's window. | 
                  
                    | DocumentsProvider | Base class for a document provider. | 
                  
                    | DreamService | Extend this class to implement a custom dream (available to the user as a "Daydream"). | 
                  
                    | ExpandableListActivity | An activity that displays an expandable list of items by binding to a data source implementing the ExpandableListAdapter, and exposes event handlers when the user selects an item. | 
                  
                    | Fragment | A Fragment is a piece of an application's user interface or behavior that can be placed in an Activity. | 
                  
                    | HostApduService | HostApduService is a convenience Serviceclass that can be extended to emulate an NFC card inside an Android service component. | 
                  
                    | HostNfcFService | HostNfcFService is a convenience Serviceclass that can be extended to emulate an NFC-F card inside an Android service component. | 
                  
                    | InCallService | This service is implemented by an app that wishes to provide functionality for managing phone calls. | 
                  
                    | InputMethodService | InputMethodService provides a standard implementation of an InputMethod, which final implementations can derive from and customize. | 
                  
                    | IntentService | IntentService is an extension of the Servicecomponent class that handles asynchronous requests (expressed asIntents) on demand. | 
                  
                    | IsolatedService | Base class for services that are started by ODP on a call to OnDevicePersonalizationManager#execute(ComponentName, PersistableBundle, java.util.concurrent.Executor, OutcomeReceiver)and run in an isolated process. | 
                  
                    | JobService | Entry point for the callback from the android.app.job.JobScheduler. | 
                  
                    | LauncherActivity | Displays a list of all activities which can be performed for a given intent. | 
                  
                    | ListActivity | An activity that displays a list of items by binding to a data source such as an array or Cursor, and exposes event handlers when the user selects an item. | 
                  
                    | ListFragment | A fragment that displays a list of items by binding to a data source such as an array or Cursor, and exposes event handlers when the user selects an item. | 
                  
                    | MediaBrowserService | Base class for media browser services. | 
                  
                    | MediaRoute2ProviderService | Base class for media route provider services. | 
                  
                    | MediaSession2Service | This API is not generally intended for third party application developers. | 
                  
                    | MidiDeviceService | A service that implements a virtual MIDI device. | 
                  
                    | MidiUmpDeviceService | A service that implements a virtual MIDI device for Universal MIDI Packets (UMP). | 
                  
                    | MockApplication | A mock android.app.Applicationclass. | 
                  
                    | MockContentProvider | Mock implementation of ContentProvider. | 
                  
                    | NativeActivity | Convenience for implementing an activity that will be implemented purely in native code. | 
                  
                    | NotificationListenerService | A service that receives calls from the system when new notifications are posted or removed, or their ranking changed. | 
                  
                    | OffHostApduService | OffHostApduService is a convenience Serviceclass that can be extended to describe one or more NFC applications that are residing off-host, for example on an embedded secure element or a UICC. | 
                  
                    | PreferenceActivity | This is the base class for an activity to show a hierarchy of preferences to the user. | 
                  
                    | PreferenceFragment | Shows a hierarchy of Preferenceobjects as lists. | 
                  
                    | PrintService |  This is the base class for implementing print services. | 
                  
                    | QuickAccessWalletService | A QuickAccessWalletServiceprovides a list ofWalletCards shown in the Quick Access Wallet. | 
                  
                    | RecognitionService | This class provides a base class for recognition service implementations. | 
                  
                    | RemoteViewsService | The service to be connected to for a remote adapter to request RemoteViews. | 
                  
                    | SearchRecentSuggestionsProvider | This superclass can be used to create a simple search suggestions provider for your application. | 
                  
                    | Service | A Service is an application component representing either an application's desire to perform a longer-running operation while not interacting with the user or to supply functionality for other applications to use. | 
                  
                    | SettingInjectorService | Dynamically specifies the summary (subtitle) and enabled status of a preference injected into the list of app settings displayed by the system settings app  | 
                  
                    | SettingsPreferenceService | Base class for a service that exposes its settings preferences to external access. | 
                  
                    | SliceProvider | A SliceProvider allows an app to provide content to be displayed in system spaces. | 
                  
                    | SpellCheckerService | SpellCheckerService provides an abstract base class for a spell checker. | 
                  
                    | TabActivity | For apps developing against android.os.Build.VERSION_CODES#HONEYCOMBor later, tabs are typically presented in the UI using the newActionBar.newTab()and related APIs for placing tabs within their action bar area. | 
                  
                    | TextToSpeechService | Abstract base class for TTS engine implementations. | 
                  
                    | TileService | A TileService provides the user a tile that can be added to Quick Settings. | 
                  
                    | TvAdService | The TvAdService class represents a TV client-side advertisement service. | 
                  
                    | TvInputService | The TvInputService class represents a TV input or source such as HDMI or built-in tuner which provides pass-through video or broadcast TV programs. | 
                  
                    | TvInteractiveAppService | A TV interactive application service is a service that provides runtime environment and runs TV interactive applications. | 
                  
                    | VisualVoicemailService | This service is implemented by dialer apps that wishes to handle OMTP or similar visual voicemails. | 
                  
                    | VoiceInteractionService | Top-level service of the current global voice interactor, which is providing support for hotwording, the back-end of a android.app.VoiceInteractor, etc. | 
                  
                    | VoiceInteractionSession | An active voice interaction session, providing a facility for the implementation to interact with the user in the voice interaction layer. | 
                  
                    | VoiceInteractionSessionService | An active voice interaction session, initiated by a VoiceInteractionService. | 
                  
                    | VpnService | VpnService is a base class for applications to extend and build their own VPN solutions. | 
                  
                    | VrListenerService | A service that is bound from the system while running in virtual reality (VR) mode. | 
                  
                    | WallpaperService | A wallpaper service is responsible for showing a live wallpaper behind applications that would like to sit on top of it. | 
                  
                    | WebViewFragment | A fragment that displays a WebView. |