I simply cut down on all high carb stuff initially, and since then for anything else have used Google, online supermarket nutritional information and/or packaging if relevant. I know roughly what and how much of it I should eat,but don't actually worry over a daily intake figure, and generally rely on my meter to tell me how my glucose levels are doing, or my scales if I want to lose more weight.
I did use online logging software for a short time, but didn't find it was really worth the additional time and effort involved. Like @Mr Pot I'd not use apps, etc, which tend to rely on user iinput.
Robbity