According to a source, the iPhone 15 Pro Max may have an extra bright display. It would be a new generation display from Samsung. Samsung has been supplying the screens for iPhones for years. 
Benjamin Kuijten | iCulture.nl – 8 February 2023, 11:41 whatsappfacebooktwittertelegramlinkedinmailprint
In recent years, Apple has improved the screens of the iPhones in a number of areas. Last year, for example, an always-on function was added, while the notch made way for the Dynamic Island. But the specs of the screen itself are also regularly tinkered with, especially the brightness. This year it could just be the case again, says a source. And especially specifically for the iPhone 15 Pro Max, because that model may have a brighter screen.
‘iPhone 15 Pro Max with brighter screen up to 2500 nits’
The information comes from rumored ShrimpApplePro. In recent years, this account has made several correct predictions, although it is sometimes wrong. In a recent tweet, he says that the iPhone 15 Pro Max will get a new type of display from Samsung. This screen has a maximum brightness of 2500 nits. If the information is correct, this means that the iPhone 15 Pro Max will have the brightest screen in an iPhone ever.
Potentially will be on iPhone 15 Pro Max… https://t.co/PgCMBDF61K
— ShrimpApplePro 🍤 Vtuber (@VNchocoTaco) February 7, 2023
Currently, the iPhone 14 Pro and iPhone 14 Pro Max have a maximum brightness of 1000 nits in normal use, 1600 nits with HDR content and 2000 nits outdoors. In the case of outdoor use, this could therefore be upgraded to 2500 nits, if the information is correct. It is also remarkable that the source explicitly only speaks about the iPhone 15 Pro Max. Normally the Pro models have the same specs, but that could be different this year.
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There are already several rumors about functions that will only be available on the iPhone 15 Pro (Max). In this article we collect them so that you know which features are unique to the more expensive iPhone 15 models. For example, the physical buttons would be missing on the Pro models and they will receive faster data transfer via USB-C.
For example, the iPhone 15 Pro Max is the only model to receive a periscopic camera lens, sources say. If Apple also adds a higher brightness for the screen, this model distinguishes itself from the iPhone 15 Pro in an extra area. Lately there have been rumors that Apple chooses a different name for this model, such as iPhone 15 Ultra. But it seems that the Ultra name will not be used until 2024, so this year's largest and most expensive iPhone will still be called iPhone 15 Pro Max.
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Apple is expected to release the iPhone 15 Pro Max in the fall of 2023. It is the successor to the iPhone 14 Pro Max and again offers the largest screen. But what else is new and what are the rumors saying? You can read everything we already know about the iPhone 15 Pro Max here.