Since the explosion of Web 2.0 applications over the last few years, some have been discussing how this technology can be applied to mobile devices. Probably the first technology to cross over onto mobile devices was the blog, resulting in the term moblog. Ajit Jaokar’s Open Gardens blog, takes this further, suggesting adapted versions of del.icio.us and flickr for mobile devices. The usage of mobile devices can potentially affect tagging and sharing data. For example, tags for a visual image could be added at the point when the image is captured, based on physical location, time, and data from other users. Sharing data between mobile devices, for example using Bluetooth, would also depend on physical location: in fact data could be fixed to particular locations, a practice known as ‘air graffiti’ or ‘splash messaging’ and enabled by a combination of spatial information and mapping feeds. Other suggestions, including one for a 'pocket wiki' for syncing wikis written with mobile devices have also been put forward by the blog Web 2.5. While critics point to the difficulties of transferring Web 2.0 concepts such as open standards to the mobile web, advocates present it as a means of bringing information down to the user rather than pushing information up onto the web.