Update README.md

Author: agonper

README.md

@@ -40,12 +40,19 @@ android {
 
 ## Installation
 
-Run the following command in your project's root folder:
+Run the following command in your project's root folder.
+
+NS7+:
 
 ```javascript
 tns plugin add nativescript-context-apis
 ```
 
+NS6:
+```javascript
+tns plugin add nativescript-context-apis@1.0.3
+```
+
 (Optional) You'll need RxJS also to properly work with geolocation streams
 
 ```javascript