diff --git a/Auth0.xcodeproj/project.pbxproj b/Auth0.xcodeproj/project.pbxproj
index 288931a9..fac1b98d 100644
--- a/Auth0.xcodeproj/project.pbxproj
+++ b/Auth0.xcodeproj/project.pbxproj
@@ -146,6 +146,9 @@
 		5CB41D8223D611AE00074024 /* ClaimValidatorsSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5CB41D8123D611AE00074024 /* ClaimValidatorsSpec.swift */; };
 		5CB41D8323D611AE00074024 /* ClaimValidatorsSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5CB41D8123D611AE00074024 /* ClaimValidatorsSpec.swift */; };
 		5CB41D8423D611AE00074024 /* ClaimValidatorsSpec.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5CB41D8123D611AE00074024 /* ClaimValidatorsSpec.swift */; };
+		5CDB7FA723FC78A300AE8B42 /* AuthenticationAPISpec.m in Sources */ = {isa = PBXBuildFile; fileRef = 5FCCC3101CF4D4FF00901E2E /* AuthenticationAPISpec.m */; };
+		5CDB7FA823FC78CF00AE8B42 /* AuthenticationAPISpec.m in Sources */ = {isa = PBXBuildFile; fileRef = 5FCCC3101CF4D4FF00901E2E /* AuthenticationAPISpec.m */; };
+		5CDB7FAC23FC7AC200AE8B42 /* A0WebAuthSpec.m in Sources */ = {isa = PBXBuildFile; fileRef = 5FBEF3DD1D07A4B700D90941 /* A0WebAuthSpec.m */; };
 		5F06DDA51CC451540011842B /* Auth0.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 5F06DD781CC448B10011842B /* Auth0.framework */; };
 		5F06DDB41CC451700011842B /* Auth0.framework in Frameworks */ = {isa = PBXBuildFile; fileRef = 5F06DD851CC448C90011842B /* Auth0.framework */; };
 		5F06DDC91CC66B710011842B /* Auth0.swift in Sources */ = {isa = PBXBuildFile; fileRef = 5F06DDC81CC66B710011842B /* Auth0.swift */; };
@@ -1757,7 +1760,7 @@
 			);
 			runOnlyForDeploymentPostprocessing = 0;
 			shellPath = /bin/sh;
-			shellScript = "AUTH0_PLIST=\"${SRCROOT}/Auth0.plist\"\nif [ -f $AUTH0_PLIST ];\nthen\ncp \"$AUTH0_PLIST\" \"${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app\"\nfi";
+			shellScript = "AUTH0_PLIST=\"${SRCROOT}/Auth0.plist\"\nif [ -f $AUTH0_PLIST ];\nthen\ncp \"$AUTH0_PLIST\" \"${BUILT_PRODUCTS_DIR}/${PRODUCT_NAME}.app/Contents/Resources\"\nfi\n";
 		};
 		5BEDE1801EC213C10007300D /* Carthage */ = {
 			isa = PBXShellScriptBuildPhase;
@@ -1946,7 +1949,9 @@
 				5CB41D6923D0BAD600074024 /* IDTokenSignatureValidatorSpec.swift in Sources */,
 				5FADB60F1CED7E5200D4BB50 /* UserPatchAttributesSpec.swift in Sources */,
 				5C4F553523C9124200C89615 /* JWKSpec.swift in Sources */,
+				5CDB7FAC23FC7AC200AE8B42 /* A0WebAuthSpec.m in Sources */,
 				5FA250541D4A85A200C544FA /* WebAuthErrorSpec.swift in Sources */,
+				5CDB7FA723FC78A300AE8B42 /* AuthenticationAPISpec.m in Sources */,
 				5CB41D7623D0C15000074024 /* IDTokenValidatorBaseSpec.swift in Sources */,
 				5B9262C31ECF0CC200F4F6D3 /* BioAuthenticationSpec.swift in Sources */,
 				5FBBF0381CC964BC0024D2AF /* Matchers.swift in Sources */,
@@ -1983,6 +1988,7 @@
 				5FBBF03C1CC96AA70024D2AF /* Responses.swift in Sources */,
 				5FADB6101CED7E5200D4BB50 /* UserPatchAttributesSpec.swift in Sources */,
 				5FBBF0391CC964BC0024D2AF /* Matchers.swift in Sources */,
+				5CDB7FA823FC78CF00AE8B42 /* AuthenticationAPISpec.m in Sources */,
 				5CB41D6A23D0BAD700074024 /* IDTokenSignatureValidatorSpec.swift in Sources */,
 				5F93BC0C1CC6B0DE0031519F /* Auth0Spec.swift in Sources */,
 				5C4F552F23C9123000C89615 /* Generators.swift in Sources */,
diff --git a/Auth0/SafariWebAuth.swift b/Auth0/SafariWebAuth.swift
index 394590b8..102639ee 100644
--- a/Auth0/SafariWebAuth.swift
+++ b/Auth0/SafariWebAuth.swift
@@ -43,6 +43,17 @@ class SafariWebAuth: WebAuth {
     var nonce: String?
     var leeway: Int = 60 * 1000 // Default leeway is 60 seconds
     var maxAge: Int?
+
+    lazy var redirectURL: URL? = {
+        let bundleIdentifier = Bundle.main.bundleIdentifier ?? SafariWebAuth.NoBundleIdentifier
+        var components = URLComponents(url: self.url, resolvingAgainstBaseURL: true)
+        components?.scheme = self.universalLink ? "https" : bundleIdentifier
+        return components?.url?
+            .appendingPathComponent("ios")
+            .appendingPathComponent(bundleIdentifier)
+            .appendingPathComponent("callback")
+    }()
+
     private var authenticationSession = true
     private var safariPresentationStyle = UIModalPresentationStyle.fullScreen
 
@@ -93,6 +104,11 @@ class SafariWebAuth: WebAuth {
         return self
     }
 
+    func redirectURL(_ redirectURL: URL) -> Self {
+        self.redirectURL = redirectURL
+        return self
+    }
+
     func nonce(_ nonce: String) -> Self {
         self.nonce = nonce
         return self
@@ -124,10 +140,8 @@ class SafariWebAuth: WebAuth {
     }
 
     func start(_ callback: @escaping (Result<Credentials>) -> Void) {
-        guard
-            let redirectURL = self.redirectURL, !redirectURL.absoluteString.hasPrefix(SafariWebAuth.NoBundleIdentifier)
-            else {
-                return callback(Result.failure(error: WebAuthError.noBundleIdentifierFound))
+        guard let redirectURL = self.redirectURL else {
+            return callback(Result.failure(error: WebAuthError.noBundleIdentifierFound))
         }
         if self.responseType.contains(.idToken) {
             guard self.nonce != nil else { return callback(Result.failure(error: WebAuthError.noNonceProvided)) }
@@ -136,7 +150,6 @@ class SafariWebAuth: WebAuth {
         let state = self.parameters["state"] ?? generateDefaultState()
         let authorizeURL = self.buildAuthorizeURL(withRedirectURL: redirectURL, defaults: handler.defaults, state: state)
 
-        #if swift(>=3.2)
         if #available(iOS 11.0, *), self.authenticationSession {
             let session = SafariAuthenticationSession(authorizeURL: authorizeURL, redirectURL: redirectURL, state: state, handler: handler, finish: callback, logger: logger)
             logger?.trace(url: authorizeURL, source: "SafariAuthenticationSession")
@@ -149,14 +162,6 @@ class SafariWebAuth: WebAuth {
             logger?.trace(url: authorizeURL, source: "Safari")
             self.storage.store(session)
         }
-        #else
-            let (controller, finish) = newSafari(authorizeURL, callback: callback)
-            let session = SafariSession(controller: controller, redirectURL: redirectURL, state: state, handler: handler, finish: finish, logger: self.logger)
-            controller.delegate = session
-            self.presenter.present(controller: controller)
-            logger?.trace(url: authorizeURL, source: "Safari")
-            self.storage.store(session)
-        #endif
     }
 
     func newSafari(_ authorizeURL: URL, callback: @escaping (Result<Credentials>) -> Void) -> (SFSafariViewController, (Result<Credentials>) -> Void) {
@@ -229,19 +234,8 @@ class SafariWebAuth: WebAuth {
                              nonce: self.nonce)
     }
 
-    var redirectURL: URL? {
-        let bundleIdentifier = Bundle.main.bundleIdentifier ?? SafariWebAuth.NoBundleIdentifier
-        var components = URLComponents(url: self.url, resolvingAgainstBaseURL: true)
-        components?.scheme = self.universalLink ? "https" : bundleIdentifier
-        return components?.url?
-            .appendingPathComponent("ios")
-            .appendingPathComponent(bundleIdentifier)
-            .appendingPathComponent("callback")
-    }
-
     func clearSession(federated: Bool, callback: @escaping (Bool) -> Void) {
         let logoutURL = federated ? URL(string: "/v2/logout?federated", relativeTo: self.url)! : URL(string: "/v2/logout", relativeTo: self.url)!
-        #if swift(>=3.2)
         if #available(iOS 11.0, *), self.authenticationSession {
             let returnTo = URLQueryItem(name: "returnTo", value: self.redirectURL?.absoluteString)
             let clientId = URLQueryItem(name: "client_id", value: self.clientId)
@@ -258,11 +252,6 @@ class SafariWebAuth: WebAuth {
             logger?.trace(url: logoutURL, source: "Safari")
             self.presenter.present(controller: controller)
         }
-        #else
-            let controller = SilentSafariViewController(url: logoutURL) { callback($0) }
-            logger?.trace(url: logoutURL, source: "Safari")
-            self.presenter.present(controller: controller)
-        #endif
     }
 }
 
diff --git a/Auth0/WebAuth.swift b/Auth0/WebAuth.swift
index a3930e0f..831e3f12 100644
--- a/Auth0/WebAuth.swift
+++ b/Auth0/WebAuth.swift
@@ -156,6 +156,12 @@ public protocol WebAuth: Trackable, Loggable {
     /// - Returns: the same WebAuth instance to allow method chaining
     func responseType(_ response: [ResponseType]) -> Self
 
+    /// Specify a redirect url to be used instead of a custom scheme
+    ///
+    /// - Parameter redirectURL: custom redirect url
+    /// - Returns: the same WebAuth instance to allow method chaining
+    func redirectURL(_ redirectURL: URL) -> Self
+
     /// Add `nonce` parameter for authentication, this is a requirement
     /// when response type `.idToken` is specified.
     ///
@@ -235,7 +241,6 @@ public protocol WebAuth: Trackable, Loggable {
      For iOS 11+ you will need to ensure that the **Callback URL** has been added
      to the **Allowed Logout URLs** section of your application in the [Auth0 Dashboard](https://manage.auth0.com/#/applications/).
 
-
      ```
      Auth0
          .webAuth()
diff --git a/Auth0Tests/WebAuthSpec.swift b/Auth0Tests/WebAuthSpec.swift
index c18dc6d0..6ab37782 100644
--- a/Auth0Tests/WebAuthSpec.swift
+++ b/Auth0Tests/WebAuthSpec.swift
@@ -267,6 +267,10 @@ class WebAuthSpec: QuickSpec {
                 expect(newWebAuth().useUniversalLink().redirectURL?.absoluteString) == "https://\(Domain)/ios/\(bundleId)/callback"
             }
 
+            it("should build with a custom url") {
+                expect(newWebAuth().redirectURL(RedirectURL).redirectURL) == RedirectURL
+            }
+
         }