17. The machine readable medium of claim 15 , wherein wherein the instructions for determining that the custom markup language tag should be replaced comprises instructions, which, when performed by the machine, causes the machine to perform the operations of determining, from a replacement table, whether one or both of the set of source code commands and the second custom markup language tag are listed as corresponding to the custom markup language tag, and using the indication as one of the criteria, wherein the replacement table comprises: a list of custom markup language tags in the first custom markup language; and for each of the tags in the list, for each supported social networking service, one of corresponding tags in a custom markup language specific to the social networking service and corresponding sets of source code commands.
15. A non-transitory machine readable medium that stores instructions which when performed by a machine, cause the machine to perform operations comprising: determining a social networking service that a social networking application is associated with; locating in the social networking application a custom markup language tag, the custom markup language tag written in a first custom markup language, the custom markup language tag specifying an instruction to implement a particular functionality; determining that the custom markup language tag should be replaced either with a set of one or more source code commands, or with a second custom markup language tag defined by the social networking service, and written in a second custom markup language, the determination based upon the determined social networking service and one or more criteria, the second custom markup language tag and the set of source code commands both containing instructions, which when executed, implement the particular functionality of the custom markup language tag in the first language; responsive to a determination that the custom markup language tag should be replaced with the set of source code commands, replacing the custom markup language tag with the set of source code commands, the set of source code commands being a source code language that is not a markup language; and responsive to a determination that the custom markup language tag should be replaced with the second custom markup language tag, replacing the custom markup language tag with the second custom markup language tag.