Google is making another big push for their web browser Chrome. These 'extensions' are being channeled to be a sort of 'apps revolution' for the web browser instead of phones. If Google's Chrome can be on the leading edge of that they may be able to increase their market share.
"There's always that email. You know the one I'm talking about: the message we're waiting for so anxiously that we end up checking our inbox 100 times a minute to see whether it's arrived. Since last Monday, I've stopped being a manic tab switcher and the F5 key on my keyboard has breathed a sigh of relief — all thanks to the Google Mail extension in Google Chrome.
Extensions are small programs that help you customize your browsing experience."