1.Side-Menu.Android
Category Slider Menu, by Yalantis .
Project address: https://github.com/Yalantis/Side-Menu.Android 
2.Context-Menu. android
can easily and quickly integrate beautiful context menus with animation effects, produced by Yalantis .
Project address: https://github.com/Yalantis/Context-Menu.Android 
3.Pull-to-Refresh.Rentals-Android
provides a simple and customizable pull-to-refresh implementation, produced by Yalantis.
Project address: https://github.com/Yalantis/Pull-to-Refresh.Rentals-Android 
4.Titanic
can display the TextView where the water level rises and falls
Project address: https://github.com/RomainPiel/Titanic 
5.AndroidSwipeLayout
sliding Layout, supports single View, ListView, GridView
Project address: https://github.com/daimajia/AndroidSwipeLayout
Demo address: Download Demo
6.Android Typeface Helper
can help you easily implement custom font library
project address: https://github.com/norbsoft/android-typeface-helper 
7.android-lockpattern
Android pattern password unlock
Project address: https://code.google.com/p/android-lockpattern/
Demo site: https://play.google.com/store/apps/details?id=group.pals.android.lib.ui.lockpattern.demo
Documentation introduction: https://code.google.com/p/android-lockpattern/wiki/QuickUse
APP example: Android boot pattern password unlock, Alipay password unlock 
8. ToggleButton
state switching Button, similar to iOS , using View to realize the
project address: https://github.com/zcweng/SwitchButton 
9. WilliamChart
library for drawing charts, Support LineChartView, BarChartView and StackBarChartView three chart types, and support Android 2.2 and above systems.
Project address: https://github.com/diogobernardino/WilliamChart
Demo address: https://play.google.com/store/apps/details?id=com.db.williamchartdemo
Demo project: https://github.com /diogobernardino/WilliamChart/tree/master/sample 
10. Implement sliding ViewPager gradient background color
project address: https://github.com/TaurusXi/GuideBackgroundColorAnimation 
11. Euclid
user resume interface, produced by Yalantis .
project address:https://github.com/Yalantis/Euclid 
12. InstaMaterial
A set of material-style concept designs for Instagram
Project address: https://github.com/frogermcs/InstaMaterial 
13. SpringIndicator
On-page instructions for sticking with bezier
Project address: https://github.com/chenupt/SpringIndicator 
14. BezierDemo
The effect of dragging and disappearing like QQ message bubbles.
Project address: https://github.com/chenupt/BezierDemo 
15. FoldableLayout
The folded stationery is opened like animation
Project address: https://github.com/alexvasilkov/FoldableLayout 
16. Taurus
pull- down refresh, produced by Yalantis. (Is it a bit familiar?)
Project address: https://github.com/Yalantis/Taurus 
17. PersistentSearch
When the search is clicked, the control displays the input box in the original position.
Project address: https://github.com/Quinny898/PersistentSearch 
18. circular-progress-button
Project address: https://github.com/dmytrodanylyk/circular-progress-button 
19. discrollview
When scrolling up and down, the child elements will present scrollView with different animation effects, which is called on the web page: parallax scrolling
Project address: https://github.com/flavienlaurent/discrollview 
20. sweet-alert-dialog
A custom dialog style with animation effects
Project address: https://github.com/pedant/sweet-alert-dialog 
21. android-floating-action-button
Material Design style floating action button
Project address: https://github.com/futuresimple/android-floating-action-button 
22. android-collapse-calendar-view
A calendar control that can switch between month view and week view
Project address: https://github.com/blazsolar/android-collapse-calendar-view 
23. NumberProgressBar
A minimalistic and sexy digital progress bar
Project address: https://github.com/daimajia/NumberProgressBar 
24. CircularProgressView
CircularProgressView is a Material-style loading prompt control implemented by custom view, compatible with any version.
Project address: https://github.com/rahatarmanahmed/CircularProgressView 
25. OriSim3D-Android
OpenGL implements various origami effects, simulating the entire process of folding a piece of paper into a boat
Project address: https://github.com/RemiKoutcherawy/OriSim3D-Android