I modded the fuel usage app that you can get over here:
The primary reason for the mod was to support fuel loads greater than 99 liters, but then I added some INI options to add new features, like comparing last laps fuel usage to the average, setting the background opacity, etc.
This new V1.16 has lots of options in the INI:
;Set Values to 1 to turn them on, 0 to turn them off, unless otherwise specified.
;background toggles showing background.
;backgroundOpacity is a float, but only 1 digit of precision (0.1, 0.2, etc). 0.0 to 1.0 are valid.
;HideIcon hides AC icon.
;backgroundBorder toggles the app border being on or off.
;showBlinking toggles blinking at the start of a lap.
;blinkHowLong sets the "time" that blinking occurs. 20 is the default, but any integer greater than 0 is ok. Larger numbers result in longer blinking.
;set showLastLapFuelUse = 1 to replace instant fuel with last laps fuel use.
;set acceptableOverage equal to a float with no more than 2 digits of precision. Default value is 0.05, but anything like 0.01, 0.1, or 0.2 should be fine.
;gui_scaling scales the size of the whole app by whatever floating point number you specify. 1.0 is the default.
background = 1
backgroundopacity = 0.7
hideicon = 1
backgroundborder = 0
showblinking = 0
blinkhowlong = 20
showlastlapfueluse = 1
acceptableoverage = 0.05
gui_scaling = 1.00
V1.17 forces two decimal places on some of the labels and writes to the screen every tenth of a second.
V1.18 removes the app title and adds a gui_scaling option to the INI
If you have any questions or ideas for improvements please let me know.