Throughout history electronics manufacturers have sold products with built-in obsolescence, or introduced new formats forcing consumers to rebut accessories and even music, films and TV shows.

Recent examples include the evolution of music, from records to tapes, CDs and downloads, each format requiring users to buy the music they already own again with the promise of better quality.

Film buffs have also seen huge changes, from VHS to laserdisc to DVD, Blu Ray and, finally, downloads.

Many gadget makers sell electronics with batteries that cannot easily be replaced, forcing users to either upgrade or pay for expensive repairs

Many gadget makers, including Apple, also sell electronics with batteries that cannot easily be replaced, forcing users to either upgrade or pay for expensive repairs.

Apple and others have also often changed the design of power supplies and other accessories with each new model, forcing consumers to buy new versions.

TV makers also warn that even the latest TVs have a limited lifespan, with on average around 100,000 hours of use before they must be replaced.

However, manufacturers hope that consumers will upgrade to the latest technology far before this happens.