Update README.md

Author: nan-li

README.md

@@ -24,5 +24,5 @@ For account issues and support please contact OneSignal support from the [OneSig
 To make things easier, we have published a demo project in the `/example` folder of this repository.
 
 #### Supports: 
-* Tested from iOS 8 to iOS 13
-* Tested from Android 4.0.3 (API level 15) to Android 9.0 (28)
+* Tested from iOS 8 to iOS 15
+* Tested from Android 4.0.3 (API level 15) to Android 12.0 (31)