Can I create a login that would direct my customers to a different page depending on the device they are on?

It is not possible for the system to direct the visitor to different pages depending on the different devices they are using.
By default, the user will start on the category page and from there they can choose the category and the products associated with that category. You may change the page the visitor starts on by going to: Admin > Site > Settings > General > Branding > Select the home page URL from the Dropdown. This will apply to all visitors irrespective of the device they are using.
Related Article: Ch. 029. Site Branding