What is the difference between some "Android Development/SDK tools"?
What is the difference between the Android Development Tools and the Android SDK Tools and the Android SDK Platform-tools and the Android SDK Build-tools?
And why not merge some of them into fewer groups? The 4 tools confused me when I downgrading/upgrading them.
Answer
SDK Tools
The SDK tools are installed with the SDK starter package and are periodically updated. The SDK tools are required if you are developing Android applications. The most important SDK tools include the Android SDK Manager (android sdk), the AVD Manager (android avd) the emulator (emulator), and the Dalvik Debug Monitor Server (ddms). A short summary of some frequently-used SDK tools is provided below.
android
Lets you manage AVDs, projects, and the installed components of the SDK.
Dalvik Debug Monitor Server (ddms)
Lets you debug Android applications.
dmtracedump
Generates graphical call-stack diagrams from trace log files. The tool uses the Graphviz Dot utility to create the graphical output, so you need to install Graphviz before running dmtracedump. For more information on using dmtracedump, see Profiling with Traceview and dmtracedump
Draw 9-patch
Allows you to easily create a NinePatch graphic using a WYSIWYG editor. It also previews stretched versions of the image, and highlights the area in which content is allowed.
Android Emulator (emulator)
A QEMU-based device-emulation tool that you can use to design, debug, and test your applications in an actual Android run-time environment.
Hierarchy Viewer (hierarchyviewer)
Lets you debug and optimize an Android application's user interface.
hprof-conv
Converts the HPROF file that is generated by the Android SDK tools to a standard format so you can view the file in a profiling tool of your choice.
layoutopt
Lets you quickly analyze your application's layouts in order to optimize them for efficiency.
mksdcard
Helps you create a disk image that you can use with the emulator, to simulate the presence of an external storage card (such as an SD card).
Monkey
Runs on your emulator or device and generates pseudo-random streams of user events such as clicks, touches, or gestures, as well as a number of system-level events. You can use the Monkey to stress-test applications that you are developing, in a random yet repeatable manner.
monkeyrunner
Provides an API for writing programs that control an Android device or emulator from outside of Android code.
ProGuard
Shrinks, optimizes, and obfuscates your code by removing unused code and renaming classes, fields, and methods with semantically obscure names.
Systrace
Lets you analyze the execution of your application in the context of system processes, to help diagnose display and performance issues.
sqlite3
Lets you access the SQLite data files created and used by Android applications.
traceview
Provides a graphical viewer for execution logs saved by your application.
zipalign
Optimizes .apk files by ensuring that all uncompressed data starts with a particular alignment relative to the start of the file. This should always be used to align .apk files after they have been signed.
Platform Tools
The platform tools are typically updated every time you install a new SDK platform. Each update of the platform tools is backward compatible with older platforms. Usually, you directly use only one of the platform tools—the Android Debug Bridge (adb). Android Debug Bridge is a versatile tool that lets you manage the state of an emulator instance or Android-powered device. You can also use it to install an Android application (.apk) file on a device.
The other platform tools, such as aidl, aapt, dexdump, and dx, are typically called by the Android build tools or Android Development Tools (ADT), so you rarely need to invoke these tools directly. As a general rule, you should rely on the build tools or the ADT plugin to call them as needed.
Note: The Android SDK provides additional shell tools that can be accessed through adb, such as bmgr and logcat.