Last month, we promised to expand our physical-device support. We delivered on that promise, but this release is about more than new features.
Xcode 27 changed many of the foundations RocketSim depends on. We’ve spent the past weeks extending our physical-device workflows, testing our CLI and Agent Skill more thoroughly, and making RocketSim more reliable in this new Xcode era.
An agent successfully navigating an app once does not tell you much. It could be luck, or the next attempt could fail because of a duplicate button label, missing accessibility data, or an unexpected orientation.
That is why we built AgentScenarios: a deterministic iOS app containing difficult interactions we can repeat after every CLI or Agent Skill change.
Our latest benchmark combines fifteen AgentScenarios flows with five workflows inside the iOS Settings app. It covers Face ID, multi-touch input, hidden debug menus, web views, repeated labels, visual targets, and stale-screen recovery.
Compared with other tools available to control the iOS Simulator, RocketSim produced:
Over 99% less command output
About a 95% lower byte-based context estimate
About 24% less measured command time
We also keep failed scenarios visible. A benchmark should tell us what to improve, not just produce a good marketing number.
RocketSim simulating a location on a connected iPhone.
RocketSim 16 introduced capturing from a USB-connected iPhone or iPad. RocketSim 16.4 now brings many of our repeatable testing workflows to those devices as well.
With RocketSim 16.4 and Xcode 27, you can:
Open saved deep links and Universal Links
Simulate coordinates, routes, and built-in scenarios
Launch, relaunch, terminate, or uninstall recent builds
Relaunch an app using another locale
Your existing App Actions are reused, so you do not need to recreate your locations or deep links specifically for physical devices.
Location simulation runs through Xcode on real hardware. This allows you to combine it with system behaviors such as Driving Focus, Vehicle Motion Cues, and automatic time-zone changes.
These are challenging times for a developer tool like RocketSim. To be honest, more things broke across the last few releases than we would have liked.
Xcode 27 introduced Device Hub and changed how Simulators are discovered, controlled, and inspected. Some accessibility metadata that agents previously relied on can also be unavailable in the new iOS 27 runtime.
We had to adapt quickly while ensuring existing RocketSim workflows kept working.
RocketSim 16.4.2 now:
Resolves Simulators running inside Device Hub from the CLI
Returns actionable agent errors instead of hanging indefinitely
Keeps coordinate interactions and screenshots working when accessibility data is unavailable
Improves Face ID command completion
Optimizes RocketSim Connect setup for Xcode 26 and Xcode 27
These improvements do not necessarily introduce brand-new features, but they improve stability as Xcode 27 moves toward its release candidate. We’re currently focused on reliability and performance, so please reach out if you encounter any issues.
We published a complete overview of everything that changed throughout RocketSim 16: