Phonenow.net is a potentially unwanted program that controls various processes on the browser. It relies on advertising material and commercial site redirects that expose users to various sponsored material. The adware program that runs in the background can alter preferences on Google Chrome, Internet Explorer, Mozilla Firefox, Safari, so the user is constantly exposed to possibly malicious online material.
There are various sites related to the Phonenow.net site and developers, so desktop notifications caused by the adware may take you to various other pages too. The content appearing on those notifications can claim that it is related to news, promotional details, and so on. However, stopping this behavior might be difficult. You need to get rid of the potentially unwanted program fully, so the initial infection is stopped and behavior can stop immediately.