Update to Latest OS X Upgrade to the latest version of OS X . If you are upgrading from Lion to Mountain Lion, then tere’s no need to visit a store and fetch a box, and install a bunch of discs. Just click the Mac App Store icon on your Mac. Buy OS X Mountain Lion. And your Mac does the rest. Clean System and User Caches etc. Using OnyX OnyX is an utility for Mac OS X which allows you to run system maintenance, to configure some hidden parameters of the Finder, Dock, QuickTime, Safari, Mail, iTunes, login window, Spotlight, and many of Apple’s applications, to delete caches, to remove a certain number of files and folders that may become cumbersome, and more.

You may need to quickly switch between user-agent strings on the fly - when developing websites that need to work on both mobile browsers and desktop browsers user-agent switcing is a must-have. And some times you’ll expirence some archaic site blocking you because you’re not using Netscape or Internet Explorer (in an ancient version e.g. version 6). Chrome got a built-in user-agent switcher. All you need to do is to open the developer tools panel (use Ctrl+Shift+I shortcut) and click the wrench button (lower right corner) and click Overrides, and enable override user agent and elect the browser or device you want to emulate and reload the page.