The answer is yes. Your website can have problems that your app can solve, such as slow-loading pages and hard-to-fill forms. Your app will be faster by a mile and more user-friendly too. Often, this increases your conversion rate through in-app purchases.
Of course, apps offer another channel for mobile marketing through push notifications. It also increases your brand's visibility whenever people see your logo on their home screen. It builds brand recall and helps increase your sales.