Improve the README.

Some of this is quite old. Links to YouTube videos from 2015 and
websites that don't exist any more aren't so useful. Update and
rearrange.

Still lacking is an ARCHITECTURE.md that explains the repo layout. I'll
do that next.

README.md

@@ -1,64 +1,61 @@
-# NDK Samples
+# Android NDK Samples
 
 [![build](https://github.com/android/ndk-samples/workflows/build.yml/badge.svg)](https://github.com/android/ndk-samples/actions)
 
-This repository contains [Android NDK][0] samples with Android Studio
-[C++ integration](https://www.youtube.com/watch?v=f7ihSQ44WO0&feature=youtu.be).
+This repository contains sample apps that use the [Android NDK].
 
-These samples use the new
-[CMake Android plugin](https://developer.android.com/studio/projects/add-native-code.html)
-with C++ support.
+## Build and run
 
-Samples could also be built with other build systems:
+1. Clone the repository
+2. Open the whole project in Android Studio
+3. Select the sample you want to run in the top bar (you may need to sync gradle
+   first)
+4. Click the play button to run the sample
 
-- for ndk-build with Android Studio, refer to directory
-  [other-builds/ndkbuild](https://github.com/googlesamples/android-ndk/tree/master/other-builds/ndkbuild)
-- for gradle-experimental plugin, refer to directory other-builds/experimental.
-  Note that gradle-experimental does not work with unified headers yet: use NDK
-  version up to r15 and Android Studio up to version 2.3. When starting new
-  project, please use CMake or ndk-build plugin.
+You can also build the samples from the command line if you prefer. Use
+`./gradlew build` to build everything (if you're  on Windows, use
+`.\gradlew.bat` instead of `./gradlew`). For individual tasks, see
+`./gradlew tasks`.  To see the tasks for an individual sample, run the `tasks`
+task for that  directory. For example, `./gradlew :camera:basic:tasks` will
+show the tasks  for the `camera/basic` app.
 
-Additional Android Studio samples:
-
-- [Google Play Game Samples with Android Studio](https://github.com/playgameservices/cpp-android-basic-samples)
-- [Google Android Vulkan Tutorials](https://github.com/googlesamples/android-vulkan-tutorials)
-- [Android Vulkan API Basic Samples](https://github.com/googlesamples/vulkan-basic-samples)
-- [Android High Performance Audio](https://github.com/googlesamples/android-audio-high-performance)
-
-Documentation
+## Additional documentation
 
 - [Add Native Code to Your Project](https://developer.android.com/studio/projects/add-native-code.html)
-- [Configure NDK for Android Studio/Gradle Plugin](https://github.com/android/ndk-samples/wiki/Configure-NDK-Path)
+- [Configure NDK for Android Studio/Gradle Plugin](https://developer.android.com/studio/projects/configure-agp-ndk)
 - [CMake for NDK](https://developer.android.com/ndk/guides/cmake.html)
 
-Known Issues
-
-- For Studio related issues, refer to
-  [Android Studio known issues](http://tools.android.com/knownissues) page
-- For NDK issues, refer to [ndk issues](https://github.com/android/ndk/issues)
+## Support
 
-For samples using `Android.mk` build system with `ndk-build` see the
-[android-mk](https://github.com/googlesamples/android-ndk/tree/android-mk)
-branch.
+If you've found an issue with a sample and you know how to fix it, please
+[send us a PR!](CONTRIBUTING.md).
 
-## Build Steps
+If you need to report a bug, where it needs to be filed depends on the type of
+issue:
 
-- With Android Studio: "Open An Existing Android Studio Project" or "File" >
-  "Open", then navigate to & select project's build.gradle file.
-- On Command Line: set up ANDROID_HOME and ANDROID_NDK_HOME to your SDK and NDK
-  path, cd to individual sample dir, and do "gradlew assembleDebug"
+* Problems with the samples themselves:
+  https://github.com/googlesamples/android-ndk/issues
+* Problems with the OS APIs: http://b.android.com (usually the Framework
+  component)
+* Problems with NDK (that is, the compiler):
+  https://github.com/android/ndk/issues
 
-## Support
+For questions about using the NDK or the platform APIs, you can ask on:
 
-For any issues you found in these samples, please
+* [The NDK mailing list](https://groups.google.com/g/android-ndk) (best if
+  you're not sure where else to ask)
+* The [Discussions](https://github.com/android/ndk-samples/discussions) tab of
+  this repo (best for questions about the samples themselves)
+* The NDK's [Discussions](https://github.com/android/ndk/discussions) (best for
+  questions about the NDK compilers and build systems)
+* [Stack Overflow](https://stackoverflow.com/questions/tagged/android)
 
-- submit patches with pull requests, see [CONTRIBUTING.md](CONTRIBUTING.md) for
-  more details, or
-- [create bugs](https://github.com/googlesamples/android-ndk/issues/new) here.
+## Additional NDK samples:
 
-For Android NDK generic questions, please ask on
-[Stack Overflow](https://stackoverflow.com/questions/tagged/android), Android
-teams are periodically monitoring questions there.
+- [Google Play Game Samples with Android Studio](https://github.com/playgameservices/cpp-android-basic-samples)
+- [Google Android Vulkan Tutorials](https://github.com/googlesamples/android-vulkan-tutorials)
+- [Android Vulkan API Basic Samples](https://github.com/googlesamples/vulkan-basic-samples)
+- [Android High Performance Audio](https://github.com/googlesamples/android-audio-high-performance)
 
 ## License
 
@@ -80,4 +77,4 @@ specific language governing permissions and limitations under the License.
 
 [LICENSE](LICENSE)
 
-[0]: https://developer.android.com/ndk
+[Android NDK]: https://developer.android.com/ndk