Browsers for cross browser testing?
What browser should I use to test my web application for cross browser testing?
What should I focus on?
You should investigate and analyse the statistic about your customers browsers. After analyzing you will see for example the following: 80% of customers use Chrome, 15% Firefox Mozilla and 5% Internet Explorer.
So you should make the effort to test only the browsers used by your customers and look at percentages of using for each browser. Time on testing should be spent accordingly