Update README.md

Updated readme for correct instructions

Author: alekmlynek

README.md

@@ -1,17 +1,27 @@
 # Godot iOS Device Check
-Apple iOS device check implementation for iOS 10+ in Godot
+Apple iOS device check implementation for iOS 11+ in Godot
 
 You can read the full implementation here.
 https://developer.apple.com/documentation/devicecheck
 
 ## Status
-This module is under development. I will tag a 1.0 release as soon as it is
-finished.
+This module is currently in beta but should work correctly.
 
 ## Install
-- Clone/download this module into your Godot source modules folder
+- Clone this module and copy the devicecheck folder into your godot/modules folder
 - Compile the export template for iOS
 
 ## Usage
-- Coming soon
+- This module exposes a Godot singleton (DeviceCheck) with the following methods:
+
+### init
+Requires instance ID of current object for callback. Use get_instance_id() in GDScript.
+
+### is_supported
+Checks if DeviceCheck is supported on the current device. Returns true|false.
+
+### get_token
+Initiates token generation. Result returned in _callback_token_received, or _callback_token_failed.
+
+#### Refer to the example project for specific implementation details