diff --git a/App/SwiftMarkItDownAppUITests/SwiftMarkItDownAppUITests.swift b/App/SwiftMarkItDownAppUITests/SwiftMarkItDownAppUITests.swift
new file mode 100644
index 0000000..59b9173
--- /dev/null
+++ b/App/SwiftMarkItDownAppUITests/SwiftMarkItDownAppUITests.swift
@@ -0,0 +1,21 @@
+import XCTest
+
+final class SwiftMarkItDownAppUITests: XCTestCase {
+    func testDefaultHTMLSampleConvertsToMarkdown() throws {
+        let app = XCUIApplication()
+        app.launch()
+
+        let convertButton = app.buttons["convertButton"]
+        XCTAssertTrue(convertButton.waitForExistence(timeout: 10), "Convert button should be visible")
+        convertButton.tap()
+
+        let output = app.textViews["conversionOutput"]
+        XCTAssertTrue(output.waitForExistence(timeout: 10), "Markdown output editor should be visible")
+
+        let markdown = String(describing: output.value ?? output.label)
+        XCTAssertTrue(markdown.contains("# Hello from iOS"), "Expected converted heading in output, got: \(markdown)")
+        XCTAssertTrue(markdown.contains("**native Swift**"), "Expected converted emphasis in output, got: \(markdown)")
+        XCTAssertTrue(markdown.contains("[Example](https://example.com)"), "Expected converted link in output, got: \(markdown)")
+        XCTAssertFalse(markdown.contains("Ignored title"), "HTML head content should not appear in output")
+    }
+}