1. A method implemented by a server having a processor executing instructions stored in a computer-readable storage media, the method comprising: receiving, by the server, a request from a mobile device for accessing first content in a first-markup language; determining capabilities of the mobile device for receiving and viewing the first content; processing the first content, by the server, based on the determined capabilities of the mobile device by: identifying certain types of markup tags and scripts in the first content as not meeting a predetermined safety criteria threshold; correcting the first content by removing from the first content the certain types of markup tags and scripts that do not meet the predetermined safety criteria threshold prior to transcoding; transcoding the first content from the first-markup language into a second-markup language that is supported by the determined capabilities of the mobile device; identifying in the first content an original uniform resource locator (URL) reference to second content stored at an external content source, the external content source comprising an external content provider in communication with the server via a network; rewriting the original URL reference in the first content to be directed to a proxy URL of the server to enable the server to act as a proxy to the second content at the external content source; replacing the original URL reference with a proxy URL reference that references the proxy URL in the first content transcoded into the second-markup language; and providing, to the mobile device, the first content transcoded into the second-markup language having the proxy URL reference, so that when the mobile device attempts to access the second content, the mobile device is directed to the server instead of the external content provider.
2. The method as described in claim 1 , further comprising inserting a resized image link into the first content transcoded into the second-markup language based on the determining.