Update README.md - new latest apk

Author: senzhk

README.md

@@ -25,7 +25,8 @@ ADBKeyboard will help in these cases, especially in device automation and testin
 
 Download APK from release page
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-* APK download: [https://github.com/senzhk/ADBKeyBoard/blob/master/ADBKeyboard.apk]
+* [Dev] Latest APK download: [https://github.com/senzhk/ADBKeyBoard/releases/download/v2.4-dev/keyboardservice-debug.apk]
+* [Old] Release APK download: [https://github.com/senzhk/ADBKeyBoard/blob/master/ADBKeyboard.apk]
 
 Build and install APK
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