watchOS 26.4 beta 2 is now available for developers, as Apple continues its 26.4 testing cycle. The first developer beta arrived about a week earlier, and this second build keeps the rollout moving for Apple Watch testers.
This update targets developers, so you should expect the usual beta tradeoffs: rough edges, possible app glitches, and battery hit on some watches. If you rely on your Apple Watch every day, install it on a secondary device.
Beta 2 carries build number 23T5221e, and it is available now through the developer update path.
How to update watchOS 26.4 beta 2
- Back up your iPhone that pairs with the Apple Watch (the watch backup happens through the iPhone).
- On your iPhone, open Watch app.
- Tap General.
- Tap Software Update.
- Tap Beta Updates (or Beta Updates / Developer Beta, depending on what you see).
- Select the watchOS 26.4 Developer Beta track.
- Go back, then download and install the update.
Keep your Apple Watch on its charger and near your iPhone, with Wi-Fi enabled, until the install finishes.
Changes in watchOS 26.4 beta 2
Apple has not highlighted big new user-facing additions with this second build. In most beta cycles, this stage focuses on fixing issues found in the first beta and smoothing performance before broader testing expands.
If you build or test watch apps, treat beta 2 as a stability pass. Re-test notifications, complications, background refresh, workout integrations, and any paired iPhone flows that depend on watch connectivity.
If you spot bugs, file them through the standard developer feedback channels so they land while the 26.4 cycle is still active.
Let us know in the comments if you noticed any changes in watchOS 26.4 beta 2, or if it fixed an issue you hit on beta 1.
The initial iOS 26.4 beta introduced a Bluetooth connectivity issue between my Apple Watch Ultra 2 and iPhone 16 Pro. The watch would not maintain a stable Bluetooth connection for more than a few minutes, which caused Siri requests on the watch—such as “What’s the weather?” or “Set an alarm/reminder”—to hang and fail.
As a temporary workaround, toggling Bluetooth off on the iPhone, waiting about 10 seconds, and turning it back on would restore functionality, but only briefly before the connection degraded again.
After installing the iOS 26.4.2 updates, the Bluetooth connection appears stable so far (approximately 1–2 hours of testing), and the watch is currently responding normally to these requests. I submitted a Feedback report to Apple, but I have not received any response.