diff --git a/aws-auth-cognito/src/test/java/com/amplifyframework/auth/cognito/featuretest/generators/testcasegenerators/SignInTestCaseGenerator.kt b/aws-auth-cognito/src/test/java/com/amplifyframework/auth/cognito/featuretest/generators/testcasegenerators/SignInTestCaseGenerator.kt
index 1ef909297e..a5eb5b284c 100644
--- a/aws-auth-cognito/src/test/java/com/amplifyframework/auth/cognito/featuretest/generators/testcasegenerators/SignInTestCaseGenerator.kt
+++ b/aws-auth-cognito/src/test/java/com/amplifyframework/auth/cognito/featuretest/generators/testcasegenerators/SignInTestCaseGenerator.kt
@@ -113,7 +113,7 @@ object SignInTestCaseGenerator : SerializableProvider {
         ).toJsonElement()
     )
 
-    private val mockedCustomChallengeResponse = MockResponse(
+    private val mockedRespondToAuthCustomChallengeResponse = MockResponse(
         CognitoType.CognitoIdentityProvider,
         "respondToAuthChallenge",
         ResponseType.Success,
@@ -121,7 +121,10 @@ object SignInTestCaseGenerator : SerializableProvider {
             "session" to "someSession",
             "challengeName" to "CUSTOM_CHALLENGE",
             "challengeParameters" to mapOf(
-                "Code" to "1234"
+                "SALT" to "abc",
+                "SECRET_BLOCK" to "secretBlock",
+                "SRP_B" to "def",
+                "USERNAME" to username
             )
         ).toJsonElement()
     )
@@ -185,8 +188,8 @@ object SignInTestCaseGenerator : SerializableProvider {
                 "additionalInfo" to mapOf(
                     "SALT" to "abc",
                     "SECRET_BLOCK" to "secretBlock",
-                    "USERNAME" to "username",
-                    "SRP_B" to "def"
+                    "SRP_B" to "def",
+                    "USERNAME" to username
                 )
             )
         ).toJsonElement()
@@ -275,7 +278,7 @@ object SignInTestCaseGenerator : SerializableProvider {
             "SignedOut_Configured.json",
             mockedResponses = listOf(
                 mockedInitiateAuthForCustomAuthWithoutSRPResponse,
-                mockedCustomChallengeResponse
+                mockedRespondToAuthCustomChallengeResponse
             )
         ),
         api = API(
@@ -295,5 +298,33 @@ object SignInTestCaseGenerator : SerializableProvider {
         )
     )
 
-    override val serializables: List<Any> = listOf(baseCase, challengeCase, deviceSRPTestCase, customAuthCase)
+    private val customAuthWithSRPCase = FeatureTestCase(
+        description = "Test that Custom Auth signIn invokes proper cognito request and returns password challenge",
+        preConditions = PreConditions(
+            "authconfiguration.json",
+            "SignedOut_Configured.json",
+            mockedResponses = listOf(
+                mockedInitiateAuthResponse,
+                mockedRespondToAuthCustomChallengeResponse
+            )
+        ),
+        api = API(
+            AuthAPI.signIn,
+            params = mapOf(
+                "username" to username,
+                "password" to "",
+            ).toJsonElement(),
+            options = mapOf(
+                "signInOptions" to mapOf("authFlow" to AuthFlowType.CUSTOM_AUTH_WITH_SRP.toString())
+            ).toJsonElement()
+        ),
+        validations = listOf(
+            mockedSignInCustomAuthChallengeExpectation,
+            ExpectationShapes.State("CustomSignIn_SigningIn.json")
+        )
+    )
+
+    override val serializables: List<Any> = listOf(
+        baseCase, challengeCase, deviceSRPTestCase, customAuthCase, customAuthWithSRPCase
+    )
 }
diff --git a/aws-auth-cognito/src/test/resources/feature-test/states/CustomSignIn_SigningIn.json b/aws-auth-cognito/src/test/resources/feature-test/states/CustomSignIn_SigningIn.json
index e69e8f6662..5ccb17e359 100644
--- a/aws-auth-cognito/src/test/resources/feature-test/states/CustomSignIn_SigningIn.json
+++ b/aws-auth-cognito/src/test/resources/feature-test/states/CustomSignIn_SigningIn.json
@@ -9,7 +9,7 @@
         "authChallenge": {
           "challengeName": "CUSTOM_CHALLENGE",
           "username": "username",
-          "session": null,
+          "session": "someSession",
           "parameters": {
             "SALT": "abc",
             "SECRET_BLOCK": "secretBlock",
diff --git a/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_custom_challenge.json b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_custom_challenge.json
new file mode 100644
index 0000000000..22049673b4
--- /dev/null
+++ b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_custom_challenge.json
@@ -0,0 +1,73 @@
+{
+    "description": "Test that Custom Auth signIn invokes proper cognito request and returns custom challenge",
+    "preConditions": {
+        "amplify-configuration": "authconfiguration.json",
+        "state": "SignedOut_Configured.json",
+        "mockedResponses": [
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "initiateAuth",
+                "responseType": "success",
+                "response": {
+                    "challengeName": "CUSTOM_CHALLENGE",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username"
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "respondToAuthChallenge",
+                "responseType": "success",
+                "response": {
+                    "session": "someSession",
+                    "challengeName": "CUSTOM_CHALLENGE",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username"
+                    }
+                }
+            }
+        ]
+    },
+    "api": {
+        "name": "signIn",
+        "params": {
+            "username": "username",
+            "password": ""
+        },
+        "options": {
+            "signInOptions": {
+                "authFlow": "CUSTOM_AUTH_WITHOUT_SRP"
+            }
+        }
+    },
+    "validations": [
+        {
+            "type": "amplify",
+            "apiName": "signIn",
+            "responseType": "success",
+            "response": {
+                "isSignedIn": false,
+                "nextStep": {
+                    "signInStep": "CONFIRM_SIGN_IN_WITH_CUSTOM_CHALLENGE",
+                    "additionalInfo": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username"
+                    }
+                }
+            }
+        },
+        {
+            "type": "state",
+            "expectedState": "CustomSignIn_SigningIn.json"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_password_challenge.json b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_password_challenge.json
new file mode 100644
index 0000000000..36e642f1f5
--- /dev/null
+++ b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Custom_Auth_signIn_invokes_proper_cognito_request_and_returns_password_challenge.json
@@ -0,0 +1,74 @@
+{
+    "description": "Test that Custom Auth signIn invokes proper cognito request and returns password challenge",
+    "preConditions": {
+        "amplify-configuration": "authconfiguration.json",
+        "state": "SignedOut_Configured.json",
+        "mockedResponses": [
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "initiateAuth",
+                "responseType": "success",
+                "response": {
+                    "challengeName": "PASSWORD_VERIFIER",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username",
+                        "USER_ID_FOR_SRP": "userId"
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "respondToAuthChallenge",
+                "responseType": "success",
+                "response": {
+                    "session": "someSession",
+                    "challengeName": "CUSTOM_CHALLENGE",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username"
+                    }
+                }
+            }
+        ]
+    },
+    "api": {
+        "name": "signIn",
+        "params": {
+            "username": "username",
+            "password": ""
+        },
+        "options": {
+            "signInOptions": {
+                "authFlow": "CUSTOM_AUTH_WITH_SRP"
+            }
+        }
+    },
+    "validations": [
+        {
+            "type": "amplify",
+            "apiName": "signIn",
+            "responseType": "success",
+            "response": {
+                "isSignedIn": false,
+                "nextStep": {
+                    "signInStep": "CONFIRM_SIGN_IN_WITH_CUSTOM_CHALLENGE",
+                    "additionalInfo": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username"
+                    }
+                }
+            }
+        },
+        {
+            "type": "state",
+            "expectedState": "CustomSignIn_SigningIn.json"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Device_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Device_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json
new file mode 100644
index 0000000000..6631e63727
--- /dev/null
+++ b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_Device_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json
@@ -0,0 +1,97 @@
+{
+    "description": "Test that Device SRP signIn invokes proper cognito request and returns success",
+    "preConditions": {
+        "amplify-configuration": "authconfiguration.json",
+        "state": "SignedOut_Configured.json",
+        "mockedResponses": [
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "initiateAuth",
+                "responseType": "success",
+                "response": {
+                    "challengeName": "PASSWORD_VERIFIER",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username",
+                        "USER_ID_FOR_SRP": "userId"
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "respondToAuthChallenge",
+                "responseType": "success",
+                "response": {
+                    "authenticationResult": {
+                        "idToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "accessToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "refreshToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "expiresIn": 300,
+                        "newDeviceMetadata": {
+                            "deviceKey": "someDeviceKey",
+                            "deviceGroupKey": "someDeviceGroupKey"
+                        }
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "confirmDevice",
+                "responseType": "success",
+                "response": {
+                }
+            },
+            {
+                "type": "cognitoIdentity",
+                "apiName": "getId",
+                "responseType": "success",
+                "response": {
+                    "identityId": "someIdentityId"
+                }
+            },
+            {
+                "type": "cognitoIdentity",
+                "apiName": "getCredentialsForIdentity",
+                "responseType": "success",
+                "response": {
+                    "credentials": {
+                        "accessKeyId": "someAccessKey",
+                        "secretKey": "someSecretKey",
+                        "sessionToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "expiration": 2342134
+                    }
+                }
+            }
+        ]
+    },
+    "api": {
+        "name": "signIn",
+        "params": {
+            "username": "username",
+            "password": "password"
+        },
+        "options": {
+        }
+    },
+    "validations": [
+        {
+            "type": "amplify",
+            "apiName": "signIn",
+            "responseType": "success",
+            "response": {
+                "isSignedIn": true,
+                "nextStep": {
+                    "signInStep": "DONE",
+                    "additionalInfo": {
+                    }
+                }
+            }
+        },
+        {
+            "type": "state",
+            "expectedState": "SignedIn_SessionEstablished.json"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_SMS_challenge.json b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_SMS_challenge.json
new file mode 100644
index 0000000000..5cc1ab4d0a
--- /dev/null
+++ b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_SMS_challenge.json
@@ -0,0 +1,69 @@
+{
+    "description": "Test that SRP signIn invokes proper cognito request and returns SMS challenge",
+    "preConditions": {
+        "amplify-configuration": "authconfiguration.json",
+        "state": "SignedOut_Configured.json",
+        "mockedResponses": [
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "initiateAuth",
+                "responseType": "success",
+                "response": {
+                    "challengeName": "PASSWORD_VERIFIER",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username",
+                        "USER_ID_FOR_SRP": "userId"
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "respondToAuthChallenge",
+                "responseType": "success",
+                "response": {
+                    "session": "someSession",
+                    "challengeName": "SMS_MFA",
+                    "challengeParameters": {
+                        "CODE_DELIVERY_DELIVERY_MEDIUM": "SMS",
+                        "CODE_DELIVERY_DESTINATION": "+12345678900"
+                    }
+                }
+            }
+        ]
+    },
+    "api": {
+        "name": "signIn",
+        "params": {
+            "username": "username",
+            "password": "password"
+        },
+        "options": {
+        }
+    },
+    "validations": [
+        {
+            "type": "amplify",
+            "apiName": "signIn",
+            "responseType": "success",
+            "response": {
+                "isSignedIn": false,
+                "nextStep": {
+                    "signInStep": "CONFIRM_SIGN_IN_WITH_SMS_MFA_CODE",
+                    "additionalInfo": {
+                    },
+                    "codeDeliveryDetails": {
+                        "destination": "+12345678900",
+                        "deliveryMedium": "SMS"
+                    }
+                }
+            }
+        },
+        {
+            "type": "state",
+            "expectedState": "SigningIn_SigningIn.json"
+        }
+    ]
+}
\ No newline at end of file
diff --git a/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json
new file mode 100644
index 0000000000..364b080df8
--- /dev/null
+++ b/aws-auth-cognito/src/test/resources/feature-test/testsuites/signIn/Test_that_SRP_signIn_invokes_proper_cognito_request_and_returns_success.json
@@ -0,0 +1,86 @@
+{
+    "description": "Test that SRP signIn invokes proper cognito request and returns success",
+    "preConditions": {
+        "amplify-configuration": "authconfiguration.json",
+        "state": "SignedOut_Configured.json",
+        "mockedResponses": [
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "initiateAuth",
+                "responseType": "success",
+                "response": {
+                    "challengeName": "PASSWORD_VERIFIER",
+                    "challengeParameters": {
+                        "SALT": "abc",
+                        "SECRET_BLOCK": "secretBlock",
+                        "SRP_B": "def",
+                        "USERNAME": "username",
+                        "USER_ID_FOR_SRP": "userId"
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentityProvider",
+                "apiName": "respondToAuthChallenge",
+                "responseType": "success",
+                "response": {
+                    "authenticationResult": {
+                        "idToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "accessToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "refreshToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "expiresIn": 300
+                    }
+                }
+            },
+            {
+                "type": "cognitoIdentity",
+                "apiName": "getId",
+                "responseType": "success",
+                "response": {
+                    "identityId": "someIdentityId"
+                }
+            },
+            {
+                "type": "cognitoIdentity",
+                "apiName": "getCredentialsForIdentity",
+                "responseType": "success",
+                "response": {
+                    "credentials": {
+                        "accessKeyId": "someAccessKey",
+                        "secretKey": "someSecretKey",
+                        "sessionToken": "eyJhbGciOiJIUzI1NiIsInR5cCI6IkpXVCJ9.eyJzdWIiOiJ1c2VySWQiLCJ1c2VybmFtZSI6InVzZXJuYW1lIiwiZXhwIjoxNTE2MjM5MDIyLCJvcmlnaW5fanRpIjoib3JpZ2luX2p0aSJ9.Xqa-vjJe5wwwsqeRAdHf8kTBn_rYSkDn2lB7xj9Z1xU",
+                        "expiration": 2342134
+                    }
+                }
+            }
+        ]
+    },
+    "api": {
+        "name": "signIn",
+        "params": {
+            "username": "username",
+            "password": "password"
+        },
+        "options": {
+        }
+    },
+    "validations": [
+        {
+            "type": "amplify",
+            "apiName": "signIn",
+            "responseType": "success",
+            "response": {
+                "isSignedIn": true,
+                "nextStep": {
+                    "signInStep": "DONE",
+                    "additionalInfo": {
+                    }
+                }
+            }
+        },
+        {
+            "type": "state",
+            "expectedState": "SignedIn_SessionEstablished.json"
+        }
+    ]
+}
\ No newline at end of file