Several brands are reportedly working on 5-inch Full HD (1080p) smartphones boasting record resolutions of 400ppi according to several US websites.

Samsung is said to be working on the "Galaxy S4", with specs halfway between the Galaxy S3 (4.8 inches) and the Galaxy Note 2 (5.55 inches), while Lenovo may be entering the fray with two new models running the latest version of Android.

HTC and LG have already announced similar projects in the pipeline, with models slated to hit the market in the first half of 2013.

More news about the trend is likely to surface at the Las Vegas CES (January 8 to 11) and at the Mobile World Congress in Barcelona (February 25 to 28).