Update README.md and pubspec.lock

.gitignore

@@ -8,7 +8,6 @@
 .buildlog/
 .history
 .svn/
-.tool-versions
 
 # IntelliJ related
 *.iml

README.md

@@ -2,9 +2,13 @@
 
 - [`flutter`](https://flutter.dev/docs/get-started/install)
 - [`gomobile`](https://godoc.org/golang.org/x/mobile/cmd/gomobile)
-- Copy `env.sh.example` to `env.sh` and update your `PATH` variable to expose both flutter and go bin directories
+- [`android-studio`](https://developer.android.com/studio)
+- [Enable NDK](https://developer.android.com/studio/projects/install-ndk) Check local.properties for current NDK version
+
+Copy env.sh.example to env.sh and update your PATH variable to expose both flutter and go bin directories
+
+  ```export PATH="$PATH:/path/to/go/bin:/path/to/flutter/bin```
 
-    ```export PATH="$PATH:/path/to/go/bin:/path/to/flutter/bin```
 
 # Formatting
 
@@ -15,6 +19,7 @@ Use:
 flutter format lib/ test/ -l 120
 ```
 
+
 # Release
 
 Update `version` in `pubspec.yaml` to reflect this release, then
@@ -30,4 +35,3 @@ Upload the android bundle to the google play store https://play.google.com/apps/
 ## iOS
 
 In xcode, Release -> Archive then follow the directions to upload to the app store. If you have issues, https://flutter.dev/docs/deployment/ios#create-a-build-archive
-