Apple prepping a 21.5-inch iMac with 4K screen for autumn launch

Apple prepares to go big on display screen resolutions with refreshed iMacs this autumn

In addition to preparing the launch of an iPhone sporting a 3D camera, Apple is also preparing to launch a range of iMacs with 4K monitors, according to reports.

It follows the uncovering of references to Mac support for a range of new screen resolutions in the second beta of Mac OS X, version 10.11, which indicates the imminent arrival of a 21.5-inch screen iMac with the 4K display.

The machine could be launched at the same time that Apple releases its next round of iPhones, which may be brought forward from the usual September launch to August.

"Although it's light on new consumer-facing features, the latest release of the OS X El Capitan beta for developers hides references to a pair of future Apple hardware products: a new 4K version of the 21.5-inch iMac and a new Bluetooth Remote control," reports 9to5Mac.com.

The code indicates new Apple Retina displays from 2304x1440 to 4096x2304, all the way to the 5120x2880 screen resolution of the 5K display, which was unveiled with an iMac bearing a 27-inch screen late last year.

It continues: "In addition to the 4K panel reference, which is not present in any version of Yosemite, the innards of the software upgrade include references to a new Intel graphics chipset known as the Iris Pro 6200. This new, Broadwell-integrated graphics processor launched earlier this month and would be a natural fit for powering a 4K iMac."

The reference to an Intel graphics chipset may also scotch suggestions, at least for the time being, that Apple is preparing a wholesale shift from Intel to ARM-based microprocessors.

However, Apple is also working with AMD on a number of R9-based graphics processors, as well as with Intel.

Another feature that 9to5Mac claims to have found references for include a new Bluetooth Remote Control, which will support a Multi-Touch trackpad "with inertial scrolling support". It continues: "There is also a reference to what could be Force Touch support, but we are less certain about that."