Update README.md

Author: zxcpoiu

README.md

@@ -20,7 +20,12 @@ you can find demo here: https://github.com/oney/RCTWebRTCDemo
 
 ## Installation:
 
-old versions (RN < 0.40) please use version `1.5.4`  
+
+#### BREAKING NOTE:
+
+for old RN versions (RN < 0.40) please use version `1.5.4`
+
+
 **from npm package**: `npm install react-native-incall-manager`  
 **from git package**: `npm install git://github.com/zxcpoiu/react-native-incall-manager.git`  
 
@@ -251,6 +256,9 @@ note: ios only supports `auto` currently.
 | async checkRecordPermission()   | :smile: | :smile: | check record permission without promt. return Promise. see **about permission** section above |
 | async requestRecordPermission()   | :smile: | :smile: | request record permission to user. return Promise. see **about permission** section above |
 | async getAudioUriJS()   | :smile: | :smile: | get audio Uri path. this would be useful when you want to pass Uri into another module. |
+| startRingtone(`ringtone: string, ?vibrate_pattern: array, ?ios_category: string, ?seconds: number`)   | :smile: | :smile: | play ringtone. </br>`ringtone`: '_DEFAULT_' or '_BUNDLE_'</br>`vibrate_pattern`: same as RN, but does not support repeat</br>`ios_category`: ios only, if you want to use specific audio category</br>`seconds`: android only, specify how long do you want to play rather than play once nor repeat. in sec.|
+| stopRingtone()   | :smile: | :smile: | stop play ringtone if previous started via `startRingtone()` |
+| stopRingback()   | :smile: | :smile: | stop play ringback if previous started via `start()` |
 
 **Events**