1. A computer-implemented method of registering promotional materials with an Internet-based content provider, comprising: generating, by one or more processing devices, one or more advertisements, the one or more advertisements being for distribution to one or more users, each user associated with one or more devices, wherein generating comprises: identifying, by one or more processing devices, advertisement content for the one or more advertisements; generating a creative for each of the one or more advertisements based on the identified advertisement content; and designating, by the one or more processing devices, the one or more advertisements for use on a mobile platform or a non-mobile platform; receiving, by the one or more processing devices, a request for content from a user of the one or more devices; determining, by the one or more processing devices, device-specific parameters for a device associated with the request, wherein the device specific parameters are indicative of the device being configured to properly display the advertisement content and comprise a parameter that specifies a platform associated with the device and a parameter that identifies types of mark-up languages supported by the device; reformatting, by the one or more processing devices, one or more of the one or more advertisements so that the one or more advertisements can be used on a different platform, the different platform being the platform associated with the device, wherein reformatting includes truncating text included in a given advertisement and receiving one or more additional advertiser constraints related to presentation of the given advertisement to a subset of the devices associated with the different platform; determining, by the one or more processing devices, based on the device specific parameters, the request and the additional advertiser constraints, one or more of the one or more advertisements for presentation to the device; and providing, by the one or more processing devices, the determined one or more advertisements for presentation to the device.