What tools and libraries have you used for automated UI testing?

For automated user interface testing, I used the following tools and libraries:

• Selenium WebDriver — for automating web interfaces, allows writing scripts in various programming languages.
• Appium — for testing mobile applications on iOS and Android.
• TestComplete — a commercial tool with a user-friendly interface for creating UI tests.
• Cucumber — for writing tests in BDD format, which makes scenarios easier to understand.

Example of a simple Selenium test (C#):

using OpenQA.Selenium;
using OpenQA.Selenium.Chrome;

class UITest {
    static void Main() {
        IWebDriver driver = new ChromeDriver();
        driver.Navigate().GoToUrl("https://example.com");
        var element = driver.FindElement(By.Id("login"));
        element.SendKeys("username");
        driver.Quit();
    }
}