How to perform scroll operation in Android Native App by initializing Remote Web driver

static RemoteWebDriver driver =null;
AndroidDriver androidDriver=null;

@Test
public void setUp() throws Exception {
	
	

	DesiredCapabilities Capabilities = new DesiredCapabilities();

	
	Capabilities.setCapability("deviceName", "Android");

	
	Capabilities.setCapability("browserName", "Android");

	
	Capabilities.setCapability("platformVersion", "6.0");

	
	Capabilities.setCapability("platformName", "Android");

	
	Capabilities.setCapability("appPackage", "PATH");

	
	Capabilities.setCapability("appActivity", "PATH");
	

	androidDriver = new AndroidDriver(new URL("http://127.0.0.1:4444/wd/hub"), Capabilities);
	driver = androidDriver;
	
	driver.manage().timeouts().implicitlyWait(15, TimeUnit.SECONDS);

	WebElement element = driver.findElement(By.xpath("//*[@text='Skip to find your library or school now']"));
	
 if(element.getText().equals("Skip to find your library or school now"))

Failing Line ==> driver.findElement(By.xpath("//*[@text=‘Skip to find your library or school now’]")).click();

	WebDriverWait Wait = new WebDriverWait(driver, 10);
	Wait.until(ExpectedConditions.visibilityOfElementLocated(By.xpath("//*[@text='Welcome to Axis 360!']")));
	WebElement input = driver.findElement(By.xpath("//*[@text='Search for My Library']"));

Error: Null Pointer Exception