Logging only mileage (no fuel)

I need to write down odometer count every friday evening and sunday evening to log my weekend rides. I have been using this workaround in Fuelio to save odometer count that I put amount of fuel to 0.00001L (close to zero).

Could there be such feature (or there already is?) that I could just fix my odometer count from time to time without having to fill fuel ? It does not work if the amount of fuel is zero. But it luckily works if it is 0.00001L :)

Br

Robert