Apple is apparently planning a refresh of its iMac line-up, bringing 4K support to its 21.5 inch models for the first time.
9to5Mac reports that the resolution increase to 4096 x 2304 will be announced at the end of October to coincide with the launch of the next version of Mac OS, El Capitan. Apparently the refresh will (unsurprisingly) mean a faster processor and improved colour saturation too.
Whilst unconfirmed, such a move would definitely make sense. At the same time last year the 27 inch iMac was boosted to a 5K display. The suggestion has also been made that Apple will continue to make the existing 1080p iMacs alongside the new 4K models, presumably so the company can continue to offer a cheaper model - a bit like how it has continued to sell the normal 1080p 27 inch iMac alongside the 5K version. [9to5Mac]