"When you use these Google products through Free Zone on your mobile phone, you won't be charged for data. You can use Free Zone even if you haven't subscribed to a data plan with your operator. You can access Free Zone using any default phone browser. Sign in to your Google Account at http://g.co/freezone with your mobile phone in order to use Google Search, Gmail, and Google+. Free Zone should be accessed using your phone's default browser. Third party browsers (such as QQ, Opera Mini and Bolt) are not supported," informs Google.
"Since using Google+, Gmail, and Google Search is free through Free Zone, there is no limit to the amount of data you use for these Google products. You're also not charged for any links that you click on from the search results page. Important: When using Search, the page you access after clicking on a search result is free. However, if you click on a link within that article — or if a link takes you outside of Google+ or Gmail — you'll be shown a warning page alerting you of any potential charges."
Free Zone is optimized for feature phones, but it also works on smartphones. You only need to change your APN settings. If Google's description is accurate, you can use Free Zone to open almost any web page: just type the URL in Google's search box and select the first result.
{ Thanks, Florian. }