Updating web resources includes extracting web resources from the application to local files, and querying an external server for web resource updates specific to at least one operating condition of the client device. A server includes at least one processor to execute computer readable instructions to generate an update bundle for web resources downloaded in an application package by a client device, the update bundle comprising at least one update that is specific to an operating condition of the client device, and, in response to a request from the client device, send the update bundle to the client device such that an application on a client device may receive web resource updates that are specific to operating conditions of the client device in order to accomplish a reduction in application start-up time.