Observable<T>	Interface for a subject that wants to expose changes to its state with notifications.
ObservableArray<T>	Interface for an observable array of values, which can be exposed by a Subject.
ObservableArray.ArrayObserver<T>	Interface to be provided by observers of this container.
ObservableValue<T>	Interface for an observable property value, which can be exposed by a Subject.
ObservableValue.ValueObserver<T>	Interface to be provided by observers of this value.
StrictModeUtils.CallbackWithoutReturnValue	Callback to be executed without return values.
StrictModeUtils.CallbackWithReturnValue<T>	Callback to be executed with return value.
TileBoard.CancelTilesCallback	Callback for cancelling on-going tile requests
TileBoard.ViewAreaUpdateCallback	Callback for TileBoard.updateViewArea(Rect, TileBoard.ViewAreaUpdateCallback).
ZoomScrollRestorer	Interface to restore scroll position.

Accessibility	Helper methods for interacting with accessibility services.
AnnotationUtils	Utility class for enabling the functionality of Edit FAB.
AppInfo	Information about the installed app (package).
BaseParcelable	Base class for simple `Parcelable` classes.
BitmapRecycler	Holds on to wasted bitmaps for a while in the hope they can be reused.
BundleUtils	Utils to deal with s.
CollectUtils	Utilities related to Collections.
ContentUriOpener	Opens content s.
CycleRange	Cycles through a range of numbers from [0 to size-1], but starting at any number between the two.
CycleRange.Iterator	CycleRange is an `java.lang.Iterable`, this is its `java.util.Iterator`.
DrawSpec	A list of rects to be drawn, and the `Paint` to draw them with.
EnumKeyGenerator	Utility to generate `java.lang.String` keys from `java.util.Collection`s of `java.lang.Enum`s.
ExifThumbnailUtils	Handles extracting Exif data for content Uri thumbnails, which don't have exif data embedded.
ExternalLinks	Utilities for describing and opening external links.
GestureTracker	Feed me events, I'll tell you what gesture is happening.
GestureTracker.GestureHandler	A recipient for all gesture handling.
GestureTrackingView	A `FrameLayout` plus helper methods to reliably share gestures with its hierarchy, by: providing a GestureTracker that will detect what gesture is happening, regardless of where it is aimed at handling generic gesture detection and passing it on in simple callbacks forcing a priority order of handling an event bottom up (from the actual target View up to any containing View and finally the Activity), including when intercepts trigger.
GestureTrackingView.PatchedSimpleGestureHandler	A wrapping that corrects the method GestureTrackingView.PatchedSimpleGestureHandler.onScroll(MotionEvent, MotionEvent, float, float) so that it's not called with absurd values for distanceX and distanceY.
HighlightOverlay	A `Drawable` overlay that highlights given list of DrawSpec.
HighlightPaint	Paint objects used for highlighting in various contexts.
Intents	Utility functions for dealing with intents.
MathUtils	Static utility methods (like Math.min but which aren't included in Math).
Observables	A few ready-to-use Observables.
Observables.AbstractObservable<O>	A convenient way to make a Subject class observable is by inheriting this base class.
Observables.ExposedArray<V>	An array that can be read and observed.
Observables.ExposedValue<V>	A value that can be read and observed.
Observables.MultiObservers<O>	An Observable that accepts multiple observers.
PaginationUtils	Utils class for [PaginatedView]
Preconditions	Simple parameter checking.
QuickScaleBypassDecider	This class is a workaround for when Android mishandles fast scrolling as a QuickScale gesture.
RectDrawSpec	Base implementation of DrawSpec which just draws basic s.
RectUtils	Utilities related to s.
Screen	Wrapper around to give shortcut access to commonly used values.
StrictModeUtils	Utility class for temporarily disabling StrictMode to do I/O on UI threads.
SystemGestureExclusionHelper	Utility to configure system gesture exclusion rects for disabling the back gesture on the left and right sides of the screen when using gesture navigation.
ThreadUtils	Thread-related utilities.
TileBoard	A mosaic of tiles matching an image.
TileBoard.Area	Describes an area (sub-rectangle) of a tiling.
TileBoard.TileInfo	Specifies one tile of the board, by coordinates (row, column) or index in a tiles matrix.
Timer	Simple timer for profiling methods.
Toaster	Pops a toast.
Uris	Helpers with s
ZoomUtils	Utils for calculating scale and zoom operations.

CycleRange.Direction	Directions to iterate around a cycle.
GestureTracker.Gesture	A recognized user gesture.