In October, 2014, Apple officially launched the 27 inch iMac with 5K retina resolution and attracted much attention. Recognized as a masterpiece of technology but the price of this device is too high (1999 USD for the lowest configuration). Therefore, to increase sales of this product line, Apple is planning to introduce an iMac 21.5 inch Retina version with cheaper price in this fall.
This information is leaked from the latest beta version of OS X El Capitan which recently, Apple has released to developers. Accordingly, Consomac site found some photos of the new generation iMac and one of which is 21.5 inch iMac with the resolution of 4096 x 2304 pixels. But more likely, Apple will not change the design of the iMac like what they did with the previous Macbook product line.
Recently, Apple also sales off 27 inch iMac. The current price of this device is $ 1,999 (decreased about 500 USD compared to $ 2,499 at launch in October last year). However, this is only applied for the lowest configuration while users still have to pay extra if they want to own high-speed SSD.
The current price of 21.5 inch iMac version is about $ 1,099, but this model is only equipped with a full HD resolution of 1920 x 1080 pixels. 21.5 inch Retina iMac version will be more expensive than full HD version but will be better when compared with the 27 inch iMac.
Until now, Apple only gives users two choices if they want to own sharp retina display: 15 inch MacBook Pro or 27 inch iMac. 21.5-inch retina iMac model is expected to fill the gap between the two segments and gives the user the more sensible choice.