Plenty of people use their Macs with just one web browser and a single email client. But many people use different web browsers to be able to easily access multiple accounts, such as Gmail or other services, for work or for personal use. Designers need to test websites on multiple browsers. And some people use different browsers for specific uses; you may have one browser for everyday web use, and another for secure browsing.
With macOS, you can set a default web browser (you do this in macOS’s system preferences under General) or email client (do this in Mail’s preferences), and these settings determine which apps open when you click links. But when you want to open a link in another app, you generally have to copy that link, switch to the other app, then paste it. This works for URLs, but if you click a link to email someone, it won’t work at all.
Bumpr ($8 through April 15, then $15; App Store link), from Scott Ostler and designer Khoi Vinh, helps you deal with these multiple apps.
Read the rest of the article on Macworld.