fix: identify mac catalyst

[ioannisj]

💡 Motivation and Context

see: https://posthog.com/questions/i-os-app-also-available-for-mac-os-is-not-showing-any-mac-os-users-in-product-analytics

Identify as macOS when running on Mac Catalyst or compatibility mode (Designed for iPad/iPhone).

Here are the keys for the two cases:

Mac Catalyst

"$device_manufacturer": "Apple"
"$device_model": "Mac15,6"
"$device_name": "macbook-pro.local"
"$device_type": "Desktop"
"$is_emulator": false
"$is_ios_running_on_mac": false
"$is_mac_catalyst_app": true
"$os_name": "macOS Version 15.1.1 (Build 24B91)"
"$os_version": "15.1.1"

iOS App running on Mac (Designed for iPad/iPhone)

"$device_manufacturer": "Apple"
"$device_model": "Mac15,6"
"$device_name": "macbook-pro.local"
"$device_type": "Desktop"
"$is_emulator": false
"$is_ios_running_on_mac": true
"$is_mac_catalyst_app": false
"$os_name": "iPadOS"
"$os_version": "18.1"

💚 How did you test it?

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

[marandaneto]

The fix is great but we need an alternative solution here.
People use the os_name and os_version with matching values in feature flags, hogql, etc.
Maybe we need a new property to tell if it's a mac catalyst or not then? like a boolean one.

[marandaneto]

I think whether it's catalyst or not is more about the app itself and not the OS, so maybe this info should be with one of the $app_X properties. the underlying OS is still the same.

[ioannisj]

Fair point, we can add something like $app_mac_catalyst and $app_ios_on_mac (or just one of the two), but I'm wondering how much this will be overcomplicating things for people. It will maintain backwards compatibility but will introduce additional steps and conventions when generating reports.

Also, what about $device_x family? Especially $device_type - currently evaluates to either Mobile or Tablet which doesn't really reflect reality. I'm assuming people are using these properties for their reports/flags as well. Do we also keep those unchanged and continue misrepresenting these cases here?

the underlying OS is still the same

True for iOS App on Mac since it's basically the same app just running in compatibility mode on Mac. However, Mac Catalyst apps are a bit of a mix - they can have access to macos specific features and interact with macOS. i.e they share codebase with iPad code, but can add additional mac functionality as well.

It's a tricky situation, since we need to balance correctness with backwards compatibility. I think I lean towards correctness here tbh.

A potential solution could be a mix:

• keep $os_ family unchanged
• correct values for $device_ family
• add a new bool $app_ios_on_mac property for both mac catalyst and ios running on mac cases.

[marandaneto]

I think $os_ should be about the running OS on the physical device, if that's wrong, we have to fix it.
I think $device_ should be about the physical device, if that's wrong, we have to fix it.
Adding a new app flag makes sense.

[ioannisj]

Pushed some changes and updated PR body

• For both cases, $device_ reflects desktop/mac
• For Catalyst, $os_ points to macOS
• For iOS running on Mac, $os_ points to iPadOS
• Added $is_ios_running_on_mac
• Added $is_mac_catalyst_app

(will create a PR on taxonomy next)

[ioannisj]

PostHog/posthog#28019

[marandaneto]

For iOS running on Mac, $os_ points to iPadOS

@ioannisj not sure if this is correct? its a mac, so the OS is the mac os, will people think they are running the app on an ipadoS?

[ioannisj]

I may have misunderstood the feedback here.

For iOS running on Apple Silicon, there's no porting process, so I think it's essentially iOS or iPadOS running under the hood on top of Mac Catalyst. It's essentially the identical code and frameworks that runs on iPhone or iPad (docs).

It's all a bit confusing and inconsistent though because in this specific case:

• ProcessInfo.processInfo.operatingSystemVersionString returns the MacOS version - (e.g Version 15.1.1 (Build 24B91))
• ProcessInfo.processInfo.operatingSystemVersion returns iPadOS version (e.g 18.1.0)

If we want to simplify things, we can treat these two cases (Mac Catalyst, iOS running on Mac) identical and use just one additional property is_mac_catalyst_app

[marandaneto]

So again just to confirm, the os and device props should be related to the physical device.
if the app is in compat. mode, this info should go either with app props or new props.
if you want to add the info of the emulated OS in compat mode, this should go under new props, right now device and os props are meant for the physical device.

[marandaneto]

this should be os_name and not version

[ioannisj]

Just copied over exactly what we use for macOS targets here so that they match

[marandaneto]

mm i feel like the naming should be deterministic since it can be used for filtering.
having the version as part of it feels wrong.
we have os_version for that.
I'd remove from both.

[marandaneto]

what does hostName return here? this is about the device name (Model), and not the user's name or device's nickname

[ioannisj]

This is equivalent to Host.current().localizedName that we already use on macOS targets (Host is not available on Catalyst).

I think both return the computer name which could leak PII actually, which I agree is concerning. We describe $device_name, however, as "Name of the device" in taxonomy

Regarding the actual device model, we capture as $device_model

[marandaneto]

this should be the info of the physical device.
So if we're using Host.current().localizedName because device.model isn't possible, then lets keep it