If you want to buy the screen of LG Ultra Fine 4K, you can no longer do so through the Apple online store. This model of 21.5 inches which came out as benchmark in 2016 MacBook Pros onwards, stops being marketed by Apple, although it will be available through other distributors.
It was the most affordable option within the Apple store with USB-C connection, since its price is around € 700. However, 27-inch screen with 5K quality still available which is sold on the Spanish website at a price of € 1399.
Little by little, the 4-inch 21.5K model has been withdrawn. The first store to see the model disappear was the UK store. At the time of writing the article, it is not on the main websites. Everything seems to indicate that Apple considers this model amortized and remove it from the web as soon as it starts to run out of stock. Finding this screen in online stores is not an easy task, although there are still some units of the 5K model, not only at Apple, but also at Amazon.
The history of this monitor has been somewhat controversial. First, its launch was delayed, which was planned to coincide with the 2016 MacBook Pros. Almost at the end of 2016 it was released. It was the perfect monitor to connect the new MacBook Pro, as an external monitor and gain screen or as a second monitor. However, a problem with insulation It caused interference in its use if the screen was placed near the router. This led LG to change hundreds of screens.
At present, it is likely that we will see this 2019 something related to the Mac Pro and a complete renovation of the screens chosen to partner with this Mac. For these teams, the minimum screen required should be a 5k screen, and predictably Apple is working on it. It's a shame, because these 4K screens, although they would not be designed for a Mac Pro, are a more than worthy companion for a Mac mini or MacBook Air retina. At least in the market we have different options to choose from.