You're right. Most people use mobile devices much more often than laptops or PCs. For online shopping this is also relevant. That is why the absence of a mobile version of a website and/or an application for smartphones can lower your positions and reduce the number of sales. But before hiring an app development company, you should find more information about what kinds of mobile apps exist and how they differ. For example, after reading this article https://blog.griddynamics.com/pwa-research/ , I realized that I needed to get a new one for business, since the smartphone application that was created 5 years ago is no longer so convenient for users and doesn't perform all the necessary functions that needed in currently conditions.