According to MacRumors and AppleInsider, Apple’s software engineers are testing iOS 26.4 internally, leaving some visitor logs on their website. This is an OS update which is expected to be out in spring, with some possible major new features. This is not to be confused with the 4th Developer Beta of iOS 26 which was already sent to Developers.
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iOS 26.4 development timeline

• Earliest known internal testing and development at Apple: August 13th, 2025 – no known build number as of yet. This is part of the “spring” version of iOS in this development cycle, which is made concurrently with the “fall” version, iOS 26.0.
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What may roll out with iOS 26.4

There are speculations on what 26.4 would bring, but sources say it’s focused on Apple Intelligence, potential updates to Siri, and a new set of emojis. The unicode consortium confirmed what will be included in Unicode 17, although Apple will redesign them before including these.

(Above Image source: The Unicode Consortium Website – URL – 8/14/2025)

It’s hard to say in particular what iOS 26.4 will bring, but rumors say Apple Intelligence may see an upgrade. This may also include a more context-aware SIRI, power by the in-house Apple LLM.

“However, it is interesting to note that Apple is already at this phase of testing for the early 2026 release. It also seems aptly timed with new leaks shared earlier Wednesday about Apple pushing forward with robotics and home efforts.”, mentioned on AppleInsider – See URL to article.

• See Also: Apple’s Siri-enabled robots are running behind, but still coming – AppleInsider
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• See Also: Apple Launching Robot Virtual Companion in 2027 – MacRumors
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