message: Updated Readme with details about android build
diff: @@ -87,6 +87,44 @@ See section "Release channels" for more details.
  ### iOS
  See [wrapper iOS install documentation](wrappers/ios/README.md "How to install").
  +### Android
  +
  +1. Go to https://repo.sovrin.org/android/libindy/{release-channel}.
  +2. 3 architecture are supported as of now arm,arm64 and x86.
  +3. Download latest version of libindy.
  +4. Unzip archives to the directory where you want to save the `.so` files.
  +5. After unzip you will get next structure of files:
  +
  +* `Your working directory`
  + * `include`
  + * `...`
  + * `lib`
  + * `libindy.so`
  + * `libindy_shared.so`
  + * `libindy.a`
  +
  +`include` contains c-header files which contains all necessary declarations
  +that may be need for your applications.
  +
  +`lib` contains three types of binaries.
  + * `libindy.so` - This is a shared library which is statically linked with all the depenedencies.
  + You dont need to sidelaod other dependencies like zmq, sodium and openssl to android app if you use this.
  +
  + * `libindy_shared.so` - This is pure shared library. It is not dynamically linked to its dependencies.
  + You need to sideload the binaries with its dependencies. You can download the needed pre-built dependencies from [here](https://github.com/evernym/indy-android-dependencies/tree/v1.0.2)
  + * Rename this library to `libindy.so` before loading it into the app. This will help you in having the compatibility with existing wrappers.
  +
  + * `libindy.a` - This is a static library, which is compiled with NDK.
  +
  + [How to use instructions.](https://github.com/hyperledger/indy-sdk/blob/master/doc/android-build.md#usage)
  +
  +{release channel} must be replaced with rc or stable to define corresponded release channel.
  +See section "Release channels" for more details.
  +
  +Notes:
  + - We are using the [NDK16b](https://dl.google.com/android/repository/android-ndk-r16b-linux-x86_64.zip) because it is the last NDK to have support for `gnustl_shared` stl.
  + gnustl_shared is deprecated in latest NDK. gnustal_shared is needed because the dependencies are compiled using gnustal_shared and you will get build errors if more than one type of stl while compiling.
  +
  ### MacOS
  Pre-built libraries are not provided for MacOS. Please look [here](doc/mac-build.md)
  