diff --git a/app/src/main/aidl/org/monkey/d/ruffy/ruffy/driver/IRuffyService.aidl b/app/src/main/aidl/org/monkey/d/ruffy/ruffy/driver/IRuffyService.aidl
index 3baa4116e1..ded119c7b4 100644
--- a/app/src/main/aidl/org/monkey/d/ruffy/ruffy/driver/IRuffyService.aidl
+++ b/app/src/main/aidl/org/monkey/d/ruffy/ruffy/driver/IRuffyService.aidl
@@ -6,9 +6,22 @@ import org.monkey.d.ruffy.ruffy.driver.IRTHandler;
 
 interface IRuffyService {
 
-    void setHandler(IRTHandler handler);
+    void addHandler(IRTHandler handler);
+    void removeHandler(IRTHandler handler);
+
+    /** Connect to the pump
+    *
+    * @return 0 if successful, -1 otherwise
+    */
     int doRTConnect();
+
+    /** Disconnect from the pump */
     void doRTDisconnect();
+
+    /*What's the meaning of 'changed'?
+     * changed means if a button state has been changed, like btton pressed is a change and button release another*/
     void rtSendKey(byte keyCode, boolean changed);
     void resetPairing();
+    boolean isConnected();
+    boolean isBoundToPump();
 }
diff --git a/app/src/main/java/de/jotomo/ruffyscripter/RuffyScripter.java b/app/src/main/java/de/jotomo/ruffyscripter/RuffyScripter.java
index 1da4b681f4..33f52b1257 100644
--- a/app/src/main/java/de/jotomo/ruffyscripter/RuffyScripter.java
+++ b/app/src/main/java/de/jotomo/ruffyscripter/RuffyScripter.java
@@ -51,7 +51,7 @@ public class RuffyScripter {
     public RuffyScripter(final IRuffyService ruffyService) {
         this.ruffyService = ruffyService;
         try {
-            ruffyService.setHandler(mHandler);
+            ruffyService.addHandler(mHandler);
             idleDisconnectMonitorThread.start();
         } catch (RemoteException e) {
             throw new RuntimeException(e);