1. A system, comprising: at least one client device; at least one email service; and, an apparatus comprising at least one processor and at least one memory storing program code instructions, the at least one memory and program code instructions being configured to, with the at least one processor, cause the apparatus to at least: proxying at least one email resource between the at least one client device and the at least one email service; detecting a device state associated with the at least one client device; identifying, based at least in part on the device state associated with the at least one client device, at least one resource rule; and, adding at least one uniform resource locator (URL) to the at least one email resource in an instance in which it is required by the at least one resource rule.