Option   Description
Auto Add Fuel   Automatically updates the F3 blackbox with the required fuel amount when you enter pitlane in race sessions only.
Auto Add Fuel All Sessions   Automatically updates the F3 blackbox with the required fuel amount when you enter pitlane in ALL sessions. Only this or the above option should be selected, not both.
Auto Stop Fuel   Auto stops refueling the car once you have reached the required amount.
Add Contingency Laps   Add extra laps of fuel to the 'Fuel to Add' figure - Change 2 to desired laps (0.5 for half a lap, 2 for 2 laps). Not using this option means a default value of 1 will be used.
Gallons   Displays all calculations in imperial measurements. Not using this option will mean metric units will be used.
HD Messages   This option displays more characters in information messages for those using a 3.4+" screens. This does not work on 2.4" screens.
Test Remaining Laps   This option allows you to set the number of remaining laps in an offline test session (use -trl 30 for 30 laps)
Ignore Yellow Flags   Fuel consumption during the pace lap and under cautions is not included in calculations.
No Front End   This option will remove the need to have an Arduino front end
Show Weather   The weather and track conditions will be shown on the screen once you connect to the session.
Show Laps on Tires   This option adds an extra number to the completed laps box. The additional number shows the number of laps since being on pit lane.
Text to Speech   This option plays pre-recorded canned audio files for certain information messages. eg. 'Box Box Box'
Note: You can only use one text to speech option. ie. -tts or -ltts or -mltts
Live Text to Speech   This option generates live audio files for certain information messages. eg. 'We need 21.2 litres of fuel'
Note: You can only use one text to speech option. ie. -tts or -ltts or -mltts
Minimal live Text to Speech   This option generates minimal live audio files for certain information messages. (aka Heath mode) eg. 'We need 21.2 litres of fuel'
Phrases for pit window open, box this lap and how much fuel to add and leave with only
Note: You can only use one text to speech option. ie. -tts or -ltts or -mltts
Disable Cloud Upload   This option disables the uploading of the session logs to the cloud. Using this option menas the community data available at iRacingPitBoard.com is not updated.
Suppress Community Data   This prevents the community fuel burn figures from being shown for the car and track combination once you join the server.
Suppress Version Check   Prevent the checking of GitHub to see if there is a new version available.
Suppress Welcome Screen   This will disable the welcome screen that first comes up when you join a session.
Custom Port Speed   Change the port speed to one of your choosing. Default: 250000
Track tire usage   Counts the number of tires used in a race session (use -ttu). Changing left hand side tires = 2 tires
Track tire set usage   Counts the number of tires sets used in a race session (use -ttsu). Changing left hand side tires = 0.5 sets

The following string should be added to the arguments field in iAppStarter
Remember to change the com port to the one you use.