diff --git a/cmd/sanderling/main.go b/cmd/sanderling/main.go
index aafc828..53b49fa 100644
--- a/cmd/sanderling/main.go
+++ b/cmd/sanderling/main.go
@@ -23,6 +23,7 @@ type testOptions struct {
 	duration  time.Duration
 	seed      int64
 	output    string
+	clearData bool
 }
 
 const topUsage = `sanderling is a property-based UI fuzzer for mobile apps.
@@ -51,6 +52,7 @@ func parseTestArgs(args []string, stderr io.Writer) (testOptions, error) {
 	flagSet.DurationVar(&options.duration, "duration", 5*time.Minute, "total test duration")
 	flagSet.Int64Var(&options.seed, "seed", 0, "RNG seed (0 = random)")
 	flagSet.StringVar(&options.output, "output", "./runs", "output directory for traces")
+	flagSet.BoolVar(&options.clearData, "clear-data", false, "clear app data before launching so the run starts from a fresh install")
 	if err := flagSet.Parse(args); err != nil {
 		return testOptions{}, err
 	}
diff --git a/cmd/sanderling/test_run.go b/cmd/sanderling/test_run.go
index a3ffe1c..96d32e1 100644
--- a/cmd/sanderling/test_run.go
+++ b/cmd/sanderling/test_run.go
@@ -17,5 +17,6 @@ func runTestPipeline(ctx context.Context, options testOptions, stdout io.Writer)
 		Duration:  options.duration,
 		Seed:      options.seed,
 		Output:    options.output,
+		ClearData: options.clearData,
 	}, stdout)
 }
diff --git a/internal/testrun/testrun.go b/internal/testrun/testrun.go
index a960fe5..fb25818 100644
--- a/internal/testrun/testrun.go
+++ b/internal/testrun/testrun.go
@@ -29,6 +29,7 @@ type Options struct {
 	Duration  time.Duration
 	Seed      int64
 	Output    string
+	ClearData bool
 }
 
 // Execute runs the full test pipeline: bundle, launch app, verify properties.
@@ -68,7 +69,7 @@ func Execute(ctx context.Context, options Options, stdout io.Writer) error {
 	}
 	defer cleanup()
 
-	if err := activeDriver.Launch(ctx, options.BundleID, false, nil); err != nil {
+	if err := activeDriver.Launch(ctx, options.BundleID, options.ClearData, nil); err != nil {
 		return fmt.Errorf("launch app: %w", err)
 	}