Simulator

Location

It can be simulated on iOS simulator for specific lat and long or some predefined physical locations.

Xcode -> Project-Scheme -> Edit Scheme -> Run(Debug) -> Options
Core Location -> Allow Location Simulation
You can provide your custom .gpx coordinates to emulate that specific Latitude & Longitude if needed.
You can even simulate walking or moving coordinates. That location file format has different ways of simulating advance locations.

But this all depends on how the app or service tracks your location, some only take your word for it - like GPS coordinates, some correlate that data with IP addresses, some have VPN known addresses in their blocklists. Some do device discovery for eg. Home Alexa + Google Android devices which all share their IP addresses or GPS coordinates to their mothership. Which averages out their data to fizzle out your spoofed location data for accessing their geo-location specific content. It's a cat and mouse game with geotracking APIs.

API Support

Mail

Some functionality while running an app in iOS simulator won’t work due to the limited access on simulator.

For eg.

mailto:

Mind Map

deep linking

compiler directives wildcard_checks for iOS Simulator

API won’t work on simulator for opening email client with method called -canOpenURL with an error message thrown in console saying “error: "This app is not allowed to query for scheme mailto"

Commands

Erasing the simulator of iOS via xcode CLI

sudo xcrun simctl erase all

Shutting down simulators

xcrun simctl shutdown all

Health

Health data continuous workout randomized data could be accessible for testing the app.

Health app doesn’t fully synced my data to the iOS simulator. Or maybe I was missing some iCloud sync settings. I did turned on Health explicitly on “Settings” app of the simulator.

Offline Mode

Utilize the network link conditioner on Mac OS.
Network disable

Test your iOS application by simulating a bad network connection with Network Link Conditioner
simulate-a-bad-network

Directories

avanderlee | Xcode Simulator Directories Exploration

Screenshot location

I just hate screenshots default location on Desktop where my wallpaper is 100% digital black as my main coding screen is OLED TV 48 LG C1.
So when coding I like to use 21:9 aspect ratio to get wide screen effect and having that lingering screenshots just feels not right.

Storing the default location

defaults write com.apple.iphonesimulator ScreenShotSaveLocation -string ~/Documents/Screenshots

Good reference for Mac OS defaults
SO | change-the-location-of-screen-shots-saved-by-the-ios-simulator

Architecture

iOS Platforms:

iOS device "generic/platform=iOS"
Simulator "generic/platform=iOS Simulator"

Note: There a whole lot more platforms. For brevity I’m just focused on iOS platforms. Otherwise there are macOS, watchOS, tvOS, visionOS platforms.

CPU Architectures:

arm64
x86_64

find simulator Identifier

Go in Xcode status bar -> Window -> Organizer and Simulators
Check the simulator and copy the ID.

Errors

loaded CoreSimulatorService is no longer valid

loaded CoreSimulatorService is no longer valid for this process.  Simulator services will no longer be available.  Error=Error Domain=NSPOSIXErrorDomain Code=61 "Connection refused" UserInfo={NSLocalizedDescription=CoreSimulator.framework was changed while the process was running.  This is not a supported configuration and can occur if Xcode.app was updated while the process was running.  Service version (944.5) does not match expected service version (942).}
Domain: NSPOSIXErrorDomain
Code: 61

failed to launch

Failed to start launchd_sim: could not bind to session, launchd_sim may have crashed or quit responding
Domain: com.apple.SimLaunchHostService.RequestError
Code: 4

delete the simulator cache

sudo rm -rf ~/Library/Developer/CoreSimulator/Caches