"they could reduce the power used by the radio and web browser by as much as 74 per cent, and this could be a big deal in for developing countries."
Another option might be for websites to reduce the amount of irrelevant carp on their websites.
Another option might be for connectivity providers (ISPs?) to introduce ISP-side ad-blocking. Whoops.
All this sounds very similar to what pioneering UK ISP Metronet (RIP) used to do several years ago - an optional configurable filtering compressing proxy/firewall between the punter and the Internet.