diff --git a/cmd/gomobile/build.go b/cmd/gomobile/build.go
index a41e581..8737210 100644
--- a/cmd/gomobile/build.go
+++ b/cmd/gomobile/build.go
@@ -47,6 +47,9 @@
 If the package directory contains an assets subdirectory, its contents
 are copied into the output.
 
+Flag -iosversion sets the minimal version of the iOS SDK to compile against.
+The default version is 6.1.
+
 The -bundleid flag is for -target ios only and sets the bundle ID to use
 with the app; defaults to "org.golang.todo".
 
@@ -218,17 +221,18 @@
 
 // "Build flags", used by multiple commands.
 var (
-	buildA        bool   // -a
-	buildI        bool   // -i
-	buildN        bool   // -n
-	buildV        bool   // -v
-	buildX        bool   // -x
-	buildO        string // -o
-	buildGcflags  string // -gcflags
-	buildLdflags  string // -ldflags
-	buildTarget   string // -target
-	buildWork     bool   // -work
-	buildBundleID string // -bundleid
+	buildA          bool   // -a
+	buildI          bool   // -i
+	buildN          bool   // -n
+	buildV          bool   // -v
+	buildX          bool   // -x
+	buildO          string // -o
+	buildGcflags    string // -gcflags
+	buildLdflags    string // -ldflags
+	buildTarget     string // -target
+	buildWork       bool   // -work
+	buildBundleID   string // -bundleid
+	buildIOSVersion string // -iosversion
 )
 
 func addBuildFlags(cmd *command) {
@@ -237,6 +241,7 @@
 	cmd.flag.StringVar(&buildLdflags, "ldflags", "", "")
 	cmd.flag.StringVar(&buildTarget, "target", "android", "")
 	cmd.flag.StringVar(&buildBundleID, "bundleid", "org.golang.todo", "")
+	cmd.flag.StringVar(&buildIOSVersion, "iosversion", "6.1", "")
 
 	cmd.flag.BoolVar(&buildA, "a", false, "")
 	cmd.flag.BoolVar(&buildI, "i", false, "")
diff --git a/cmd/gomobile/env.go b/cmd/gomobile/env.go
index a5dc19e..f2ec576 100644
--- a/cmd/gomobile/env.go
+++ b/cmd/gomobile/env.go
@@ -113,10 +113,10 @@
 			fallthrough
 		case "arm64":
 			clang, cflags, err = envClang("iphoneos")
-			cflags += " -miphoneos-version-min=6.1"
+			cflags += " -miphoneos-version-min=" + buildIOSVersion
 		case "386", "amd64":
 			clang, cflags, err = envClang("iphonesimulator")
-			cflags += " -mios-simulator-version-min=6.1"
+			cflags += " -mios-simulator-version-min=" + buildIOSVersion
 		default:
 			panic(fmt.Errorf("unknown GOARCH: %q", arch))
 		}