update readme

README.md

@@ -1,29 +1,23 @@
-# go-tun2socks-mobile
+# go-tun2socks-build
 
-Demo for building and using `go-tun2socks` on iOS and Android.
+Demo for building and using `go-tun2socks` on Android.
 
-## Prerequisites
+## Setup
+
+* install go (only test under version 1.13.5)
+* install gomobile and init with `gomobile init -v`
+* Download Android SDK and NDK (only test under SDK 29 and NDK r20b)
 
-- macOS (iOS)
-- Xcode (iOS)
-- SDK (Android)
-- NDK (Android)
-- make
-- Go >= 1.11
-- A C compiler (e.g.: clang, gcc)
-- gomobile (https://github.com/golang/go/wiki/Mobile)
-- Other common utilities (e.g.: git)
 
 ## Build
 ```bash
+export http_proxy=http://127.0.0.1:8087
+export https_proxy=http://127.0.0.1:8087
+export ANDROID_HOME=/path/to/Android/Sdk
+export ANDROID_NDK_HOME=/path/to/Android/android-ndk-r20b
+
 go get -d ./...
 
 # Build an AAR
 make android
-
-# Build a Framework
-make ios
-
-# Both
-make
 ```