Must have Libraries - nhtechip/android-bootstrap GitHub Wiki

Overview

There are many third-party libraries for Android but several of them are "must have" libraries that are extremely popular and are often used in almost any Android project. Each has different purposes but all of them make life as a developer much more pleasant. The major libraries are listed below in a few categories.

Compatibility

ActionBarSherlock - Fully backwards compatible ActionBar support library. Widely used. Download and install as a library project.
NineOldAndroids - Fully compatible animation library that works with all versions of Android. Widely used. Download and install as a library project.
HoloEverywhere - Backport Holo theme from Android 4.2 to 2.1+

Convenience

ButterKnife - Using Java annotations, makes Android development better by simplifying common tasks. Download and install as a jar. Make sure to setup eclipse integration for this to work.
AndroidAnnotations - Framework that speeds up Android development. It takes care of the plumbing, and lets you concentrate on what's really important. By simplifying your code, it facilitates its maintenance
RoboGuice - Powerful extensions to Android using dependency injection.

Extensions

Otto - An enhanced Guava-based event bus with emphasis on Android support
EventBus - Android optimized event bus that simplifies communication between components.
Tape - Tape is a collection of queue-related classes for Android and Java

Networking

Picasso - A powerful image downloading and caching library for Android.
Ion - Powerful asynchronous networking library. Download as a jar here.
Android Async HTTP - Asynchronous networking client for loading remote content such as JSON.

ListView

PullToRefresh-ListView - Easy to use pull-to-refresh functionality for ListViews. Download and install as a library project.
StickyListHeaders - An android library for section headers that stick to the top of a ListView
ListViewAnimations - Easy way to animate ListView items

View Pager Enhancements

PagerSlidingTabStrip - An interactive indicator to navigate between the different pages of a ViewPager.
ViewPagerIndicator - Paging indicator widgets compatible with the ViewPager from the Android Support Library and ActionBarSherlock.

UI Components

SlidingMenu - Library that allows developers to easily create applications with sliding menus like those made popular in the Google+, YouTube, and Facebook apps.
Crouton - Context-sensitive, configurable alert notices much better than toasts. Download jar from here. See working sample code
AChartEngine - This is a charting software library for Android applications

Resources

Check out the following resources for finding libraries: