diff --git a/Session/Calls/Call Management/SessionCall.swift b/Session/Calls/Call Management/SessionCall.swift
index a2d0104ab..e2e8b4a20 100644
--- a/Session/Calls/Call Management/SessionCall.swift	
+++ b/Session/Calls/Call Management/SessionCall.swift	
@@ -128,6 +128,11 @@ public final class SessionCall: NSObject, WebRTCSessionDelegate {
         WebRTCSession.current = self.webRTCSession
         super.init()
         self.webRTCSession.delegate = self
+        if AppEnvironment.shared.callManager.currentCall == nil {
+            AppEnvironment.shared.callManager.currentCall = self
+        } else {
+            SNLog("[Calls] A call is ongoing.")
+        }
     }
     
     func reportIncomingCallIfNeeded(completion: @escaping (Error?) -> Void) {
@@ -147,7 +152,7 @@ public final class SessionCall: NSObject, WebRTCSessionDelegate {
     }
     
     // MARK: Actions
-    func startSessionCall(completion: (() -> Void)?) {
+    func startSessionCall() {
         guard case .offer = mode else { return }
         var promise: Promise<Void>!
         Storage.write(with: { transaction in
@@ -161,10 +166,9 @@ public final class SessionCall: NSObject, WebRTCSessionDelegate {
                 }
             }
         })
-        completion?()
     }
     
-    func answerSessionCall(completion: (() -> Void)?) {
+    func answerSessionCall() {
         guard case .answer = mode else { return }
         hasStartedConnecting = true
         if let sdp = remoteSDP {
@@ -172,7 +176,6 @@ public final class SessionCall: NSObject, WebRTCSessionDelegate {
         } else {
             isWaitingForRemoteSDP = true
         }
-        completion?()
     }
     
     func endSessionCall() {
diff --git a/Session/Calls/Call Management/SessionCallManager+CXCallController.swift b/Session/Calls/Call Management/SessionCallManager+CXCallController.swift
index c543f5026..62607e08b 100644
--- a/Session/Calls/Call Management/SessionCallManager+CXCallController.swift	
+++ b/Session/Calls/Call Management/SessionCallManager+CXCallController.swift	
@@ -2,7 +2,7 @@ import CallKit
 import SessionUtilitiesKit
 
 extension SessionCallManager {
-    public func startCall(_ call: SessionCall, completion: (() -> Void)?) {
+    public func startCall(_ call: SessionCall, completion: ((Error?) -> Void)?) {
         guard case .offer = call.mode else { return }
         let handle = CXHandle(type: .generic, value: call.sessionID)
         let startCallAction = CXStartCallAction(call: call.uuid, handle: handle)
@@ -13,17 +13,23 @@ extension SessionCallManager {
         transaction.addAction(startCallAction)
         
         reportOutgoingCall(call)
-        requestTransaction(transaction)
-        completion?()
+        requestTransaction(transaction, completion: completion)
+    }
+    
+    public func answerCall(_ call: SessionCall, completion: ((Error?) -> Void)?) {
+        let answerCallAction = CXAnswerCallAction(call: call.uuid)
+        let transaction = CXTransaction()
+        transaction.addAction(answerCallAction)
+
+        requestTransaction(transaction, completion: completion)
     }
     
-    public func endCall(_ call: SessionCall, completion: (() -> Void)?) {
+    public func endCall(_ call: SessionCall, completion: ((Error?) -> Void)?) {
         let endCallAction = CXEndCallAction(call: call.uuid)
         let transaction = CXTransaction()
         transaction.addAction(endCallAction)
 
-        requestTransaction(transaction)
-        completion?()
+        requestTransaction(transaction, completion: completion)
     }
     
     // Not currently in use
@@ -35,13 +41,14 @@ extension SessionCallManager {
         requestTransaction(transaction)
     }
     
-    private func requestTransaction(_ transaction: CXTransaction) {
+    private func requestTransaction(_ transaction: CXTransaction, completion: ((Error?) -> Void)? = nil) {
         callController.request(transaction) { error in
             if let error = error {
                 SNLog("Error requesting transaction: \(error)")
             } else {
                 SNLog("Requested transaction successfully")
             }
+            completion?(error)
         }
     }
 }
diff --git a/Session/Calls/Call Management/SessionCallManager+CXProvider.swift b/Session/Calls/Call Management/SessionCallManager+CXProvider.swift
index 3b0cfa9b7..23d69e6bc 100644
--- a/Session/Calls/Call Management/SessionCallManager+CXProvider.swift	
+++ b/Session/Calls/Call Management/SessionCallManager+CXProvider.swift	
@@ -9,18 +9,22 @@ extension SessionCallManager: CXProviderDelegate {
     public func provider(_ provider: CXProvider, perform action: CXStartCallAction) {
         AssertIsOnMainThread()
         guard let call = self.currentCall else { return action.fail() }
-        call.startSessionCall(completion: nil)
+        call.startSessionCall()
         action.fulfill()
     }
     
     public func provider(_ provider: CXProvider, perform action: CXAnswerCallAction) {
         AssertIsOnMainThread()
-        guard let _ = self.currentCall else { return action.fail() }
-        let userDefaults = UserDefaults.standard
-        if userDefaults[.hasSeenCallIPExposureWarning] {
-            showCallVC()
+        guard let call = self.currentCall else { return action.fail() }
+        if let _ = CurrentAppContext().frontmostViewController() as? CallVC {
+            call.answerSessionCall()
         } else {
-            showCallModal()
+            let userDefaults = UserDefaults.standard
+            if userDefaults[.hasSeenCallIPExposureWarning] {
+                showCallVC()
+            } else {
+                showCallModal()
+            }
         }
         action.fulfill()
     }
diff --git a/Session/Calls/Call Management/SessionCallManager.swift b/Session/Calls/Call Management/SessionCallManager.swift
index 72978f143..7e4c2ffc0 100644
--- a/Session/Calls/Call Management/SessionCallManager.swift	
+++ b/Session/Calls/Call Management/SessionCallManager.swift	
@@ -4,7 +4,19 @@ import SessionMessagingKit
 public final class SessionCallManager: NSObject {
     let provider: CXProvider
     let callController = CXCallController()
-    var currentCall: SessionCall?
+    var currentCall: SessionCall? = nil {
+        willSet {
+            if (newValue != nil) {
+                DispatchQueue.main.async {
+                    UIApplication.shared.isIdleTimerDisabled = true
+                }
+            } else {
+                DispatchQueue.main.async {
+                    UIApplication.shared.isIdleTimerDisabled = false
+                }
+            }
+        }
+    }
     
     private static var _sharedProvider: CXProvider?
     class func sharedProvider(useSystemCallLog: Bool) -> CXProvider {
@@ -46,12 +58,13 @@ public final class SessionCallManager: NSObject {
     
     public func reportOutgoingCall(_ call: SessionCall) {
         AssertIsOnMainThread()
-        self.currentCall = call
-        call.hasStartedConnectingDidChange = {
-            self.provider.reportOutgoingCall(with: call.uuid, startedConnectingAt: call.connectingDate)
-        }
-        call.hasConnectedDidChange = {
-            self.provider.reportOutgoingCall(with: call.uuid, connectedAt: call.connectedDate)
+        call.stateDidChange = {
+            if call.hasStartedConnecting {
+                self.provider.reportOutgoingCall(with: call.uuid, startedConnectingAt: call.connectingDate)
+            }
+            if call.hasConnected {
+                self.provider.reportOutgoingCall(with: call.uuid, connectedAt: call.connectedDate)
+            }
         }
     }
     
@@ -69,11 +82,11 @@ public final class SessionCallManager: NSObject {
         // Report the incoming call to the system
         self.provider.reportNewIncomingCall(with: call.uuid, update: update) { error in
             guard error == nil else {
+                self.currentCall = nil
                 completion(error)
                 Logger.error("failed to report new incoming call, error: \(error!)")
                 return
             }
-            self.currentCall = call
             completion(nil)
         }
     }
diff --git a/Session/Calls/CallVC.swift b/Session/Calls/CallVC.swift
index e724cd338..ba35b2379 100644
--- a/Session/Calls/CallVC.swift
+++ b/Session/Calls/CallVC.swift
@@ -167,6 +167,15 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
                 }
             }
         }
+        self.call.hasStartedConnectingDidChange = {
+            DispatchQueue.main.async {
+                self.callInfoLabel.text = "Connecting..."
+                self.answerButton.alpha = 0
+                UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
+                    self.answerButton.isHidden = true
+                }, completion: nil)
+            }
+        }
         self.call.hasConnectedDidChange = {
             DispatchQueue.main.async {
                 self.callInfoLabel.text = "Connected"
@@ -180,8 +189,10 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
             }
         }
         self.call.hasEndedDidChange = {
-            self.conversationVC?.showInputAccessoryView()
-            self.presentingViewController?.dismiss(animated: true, completion: nil)
+            DispatchQueue.main.async {
+                self.conversationVC?.showInputAccessoryView()
+                self.presentingViewController?.dismiss(animated: true, completion: nil)
+            }
         }
     }
     
@@ -194,9 +205,16 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
         if shouldRestartCamera { cameraManager.prepare() }
         touch(call.videoCapturer)
         titleLabel.text = self.call.contactName
-        AppEnvironment.shared.callManager.startCall(call) {
-            self.callInfoLabel.text = "Ringing..."
-            self.answerButton.isHidden = true
+        AppEnvironment.shared.callManager.startCall(call) { error in
+            DispatchQueue.main.async {
+                if let _ = error {
+                    self.callInfoLabel.text = "Can't start a call."
+                    self.endCall()
+                } else {
+                    self.callInfoLabel.text = "Ringing..."
+                    self.answerButton.isHidden = true
+                }
+            }
         }
         if shouldAnswer { answerCall() }
     }
@@ -305,12 +323,13 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
     @objc private func answerCall() {
         let userDefaults = UserDefaults.standard
         if userDefaults[.hasSeenCallIPExposureWarning] {
-            self.call.answerSessionCall{
-                self.callInfoLabel.text = "Connecting..."
-                self.answerButton.alpha = 0
-                UIView.animate(withDuration: 0.5, delay: 0, usingSpringWithDamping: 1, initialSpringVelocity: 1, options: .curveEaseIn, animations: {
-                    self.answerButton.isHidden = true
-                }, completion: nil)
+            AppEnvironment.shared.callManager.answerCall(call) { error in
+                DispatchQueue.main.async {
+                    if let _ = error {
+                        self.callInfoLabel.text = "Can't answer the call."
+                        self.endCall()
+                    }
+                }
             }
         } else {
             userDefaults[.hasSeenCallIPExposureWarning] = true
@@ -319,7 +338,12 @@ final class CallVC : UIViewController, VideoPreviewDelegate {
     }
     
     @objc private func endCall() {
-        AppEnvironment.shared.callManager.endCall(call, completion: nil)
+        AppEnvironment.shared.callManager.endCall(call) { error in
+            if let _ = error {
+                self.call.endSessionCall()
+                AppEnvironment.shared.callManager.reportCurrentCallEnded(reason: nil)
+            }
+        }
     }
     
     @objc private func minimize() {
diff --git a/Session/Calls/Views & Modals/IncomingCallBanner.swift b/Session/Calls/Views & Modals/IncomingCallBanner.swift
index 9ebdee16d..569ffdb1f 100644
--- a/Session/Calls/Views & Modals/IncomingCallBanner.swift	
+++ b/Session/Calls/Views & Modals/IncomingCallBanner.swift	
@@ -155,7 +155,11 @@ final class IncomingCallBanner: UIView, UIGestureRecognizerDelegate {
     }
     
     @objc private func endCall() {
-        AppEnvironment.shared.callManager.endCall(call) {
+        AppEnvironment.shared.callManager.endCall(call) { error in
+            if let _ = error {
+                self.call.endSessionCall()
+                AppEnvironment.shared.callManager.reportCurrentCallEnded(reason: nil)
+            }
             self.dismiss()
         }
     }
diff --git a/Session/Conversations/ConversationVC+Interaction.swift b/Session/Conversations/ConversationVC+Interaction.swift
index efc0f6ced..7be62ee46 100644
--- a/Session/Conversations/ConversationVC+Interaction.swift
+++ b/Session/Conversations/ConversationVC+Interaction.swift
@@ -31,6 +31,7 @@ extension ConversationVC : InputViewDelegate, MessageCellDelegate, ContextMenuAc
         let userDefaults = UserDefaults.standard
         if userDefaults[.hasSeenCallIPExposureWarning] {
             guard let contactSessionID = (thread as? TSContactThread)?.contactSessionID() else { return }
+            guard AppEnvironment.shared.callManager.currentCall == nil else { return }
             let call = SessionCall(for: contactSessionID, uuid: UUID().uuidString, mode: .offer)
             let callVC = CallVC(for: call)
             callVC.conversationVC = self
diff --git a/Session/Meta/AppDelegate.swift b/Session/Meta/AppDelegate.swift
index d6c994d10..afe933801 100644
--- a/Session/Meta/AppDelegate.swift
+++ b/Session/Meta/AppDelegate.swift
@@ -17,7 +17,6 @@ extension AppDelegate {
                     conversationVC.inputAccessoryView?.isHidden = true
                     conversationVC.inputAccessoryView?.alpha = 0
                     presentingVC.present(callVC, animated: true, completion: nil)
-                    return
                 }
             }
             call.reportIncomingCallIfNeeded{ error in