osName:         Android 12
                iOS
osVersion:      <android_sdk_version> e.g. 31
                <ios_version> e.g. 16.3
screenWidth:    <width> e.g. 392
screenHeight:   <height> e.g. 856
appVersion:     2.2.0+1
deviceId:       <ios_uuid>
readAheadLimit: 100

technology:   FlutterMobile
deviceMode:   mobile
deviceType:   <hardware_manufacturer> e.g. Xiaomi
              iPhone
deviceTypeModel: <android_end_user_visible_name> e.g. M2103K19PG
                 <ios_assigned_device_name> My iPhone name (iOS <= 15)
                 iPhone (iOS >= 16)
                 ...
langCode:      <language_code> e.g. en
timeZoneCode:  <timezone> e.g. Europe/Vienna
serverVersion: <supported_server_version> e.g. 2.4.0
baseUrl:       <service_url> e.g. http://www.domain.com/myapp/services/mobile

osName:         Linux x86_64
                MacIntel
                ...
screenWidth:    <width> e.g. 392
screenHeight:   <height> e.g. 856
appVersion:     2.2.0+1
deviceId:       <ios_uuid> e.g. XXXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX
readAheadLimit: 100

technology:   FlutterWeb
deviceMode:   mobileDesktop (or mobile if forced with ?mobileOnly=true)
deviceType:   chrome
              firefox
              ...
deviceTypeModel: <user_agent_string> e.g. Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/110.0.0.0 Safari/537.36

langCode:      <language_code> e.g. en
timeZoneCode:  <timezone> e.g. Europe/Vienna
serverVersion: <supported_server_version> e.g. 2.4.0
baseUrl:       <service_url> http://www.domain.com/myapp/services/mobile  
requestUri:    <browser_url> e.g. http://www.domain.com/myapp/mobile/

osName

• Web (https://developer.mozilla.org/en-US/docs/Web/API/Navigator/platform)
• Android (String “Android” with release Version e.g. “Android 12”)
• iOS (The current operating system name)

osVersion

• Android (https://developer.android.com/reference/android/os/Build.VERSION_CODES.html)
• iOS (The current operating system version)

deviceId

• Android (not available)
• iOS (UUID for device)

deviceType

• Web (browser name)
• Android (The manufacturer of the product/hardware.)
• iOS (Device model)

deviceTypeModel

• Web (User-agent string)
• Android (The end-user-visible name for the end product.)
• iOS (https://developer.apple.com/documentation/uikit/uidevice/1620015-name)

It's also possible to send custom properties from the flutter client to the application. To do this, use the Startup Request and send properties in this form:

 custom_propertyname: value

Every custom property has to use the prefix custom_. The prefix will be removed and only the propertyname will be used. The application will be able use access the value with propertyname.