diff --git a/oem/firstvoices/ios/FirstVoices.xcodeproj/project.pbxproj b/oem/firstvoices/ios/FirstVoices.xcodeproj/project.pbxproj
index 85a5f291f6..aeeaaac4ee 100644
--- a/oem/firstvoices/ios/FirstVoices.xcodeproj/project.pbxproj
+++ b/oem/firstvoices/ios/FirstVoices.xcodeproj/project.pbxproj
@@ -677,7 +677,7 @@
 				PROVISIONING_PROFILE_SPECIFIER = "";
 				SWIFT_OBJC_BRIDGING_HEADER = "";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 5.0;
+				SWIFT_VERSION = 4.2;
 			};
 			name = Debug;
 		};
@@ -701,7 +701,7 @@
 				PROVISIONING_PROFILE = "";
 				PROVISIONING_PROFILE_SPECIFIER = "";
 				SWIFT_OBJC_BRIDGING_HEADER = "";
-				SWIFT_VERSION = 5.0;
+				SWIFT_VERSION = 4.2;
 			};
 			name = Release;
 		};
@@ -728,7 +728,7 @@
 				SKIP_INSTALL = YES;
 				SWIFT_OBJC_BRIDGING_HEADER = "";
 				SWIFT_OPTIMIZATION_LEVEL = "-Onone";
-				SWIFT_VERSION = 5.0;
+				SWIFT_VERSION = 4.2;
 			};
 			name = Debug;
 		};
@@ -754,7 +754,7 @@
 				PROVISIONING_PROFILE_SPECIFIER = "";
 				SKIP_INSTALL = YES;
 				SWIFT_OBJC_BRIDGING_HEADER = "";
-				SWIFT_VERSION = 5.0;
+				SWIFT_VERSION = 4.2;
 			};
 			name = Release;
 		};