Mobile users generate ever-increasing amounts of digital data, such as photos, which they upload, while on the go, to online services. 3G connectivity enables mobile users to upload their data while on the go but drains the battery of their devices and overloads mobile service providers. Wi-Fi data offloading overcomes the aforementioned issues for delay-tolerant data, at the cost of constrained mobility for users as they are required to stay within a given area while the data is uploaded. The up-link of the broadband connection of the access point is a bottleneck and incurs significant waiting times. In this paper, we advocate the exploitation of the storage capabilities of common devices located on the Wi-Fi access point LAN, typically residential gateways, to decrease the waiting time. We propose Hoop, a system for offloading upload tasks onto such devices. Hoop operates seamlessly on http(s) post, making it highly generic; it also requires limited changes on the gateways and on the web server and none to existing protocols or browsers. Hoop is secure and, in a typical setting, reduces the waiting time by up to a factor of 46. By correlating mobility traces with the positions of the Wi-Fi access points of a major community network, we show that Hoop drastically decreases the delay between the time a photo is taken and the time it is uploaded, compared to regular Wi-Fi offloading.