A key highlight of macOS 15.4 is the introduction of automatic Mail categorization, a feature powered by Apple Intelligence. This tool sorts incoming emails into predefined categories—Primary, Transactions, Updates, and Promotions—directly on-device, ensuring privacy while streamlining inbox management. For users juggling busy email accounts, this could mean less time sifting through clutter and more focus on what matters. The feature mirrors capabilities rolled out in iOS 18.4 and iPadOS 18.4, creating a unified experience across Apple’s ecosystem.
While the categorization isn’t customizable yet, its seamless integration into the Mail app offers a practical boost for everyday use. Whether it’s tracking a shipment in Transactions or skimming Promotions for deals, the system aims to make email less of a chore—though power users might still crave deeper control.
Another notable tweak in this RC is an upgrade to Podcasts search functionality. As you type, the app now delivers live suggestions, pulling from episode titles, show descriptions, and creator names. This real-time feedback makes it easier to pinpoint specific content without wading through irrelevant results. For podcast enthusiasts on Mac, it’s a small but welcome refinement that keeps pace with the growing popularity of the medium.
SD Card Support Expands
Hardware compatibility also sees a lift with this update. Macs equipped with built-in SD card readers—specifically those running Apple silicon—now support SDUC (Secure Digital Ultra Capacity) cards exceeding 2TB. This upgrade caters to photographers, videographers, and other creatives who rely on high-capacity storage for large files. It’s a niche but meaningful addition, ensuring macOS keeps up with evolving media demands.
Stability and Final Touches
The second RC typically indicates a focus on polish rather than major feature additions. Alongside the first RC’s build (24E240), this version addresses lingering bugs and performance hiccups reported during testing. Posts on X have noted earlier issues, like Finder preview glitches in the initial RC, suggesting Apple is ironing out these wrinkles. The rapid succession of RCs—less than a week apart—underscores a push to stabilize the software ahead of its public debut, likely in early April 2025.
Why It Matters for Mac Users
For Mac owners, macOS 15.4 doesn’t reinvent the wheel but delivers targeted improvements that enhance daily workflows. Mail categorization stands out as a productivity win, especially for those tethered to their inboxes, while the Podcasts tweak and SDUC support cater to specific but growing user needs. Apple’s pro-innovation approach shines here—practical tools, not flashy overhauls, grounded in real-world utility.
As TSMC accelerates U.S. chip production for Apple silicon (a separate tech headline), software updates like this ensure Macs stay optimized for both current and future hardware. The on-device AI processing behind Mail categorization also hints at Apple’s broader strategy: leveraging its silicon edge to deliver smarter, privacy-first features.
Looking Ahead
With the second RC now in testers’ hands, macOS 15.4 is poised to hit all compatible Macs soon—possibly as early as next week, given the Friday publication cadence. Users on macOS 15.2 or later with M1 or newer chips will get the full Apple Intelligence experience, while older systems will still benefit from core updates. For now, it’s a waiting game, but one that promises a smoother, more efficient Mac experience just over the horizon.
