Ag Guardian, a cloud-based app, keeps a running total of the products you've applied to your fields.
Great for bookkeeping in relevance to the products you use and how much of it.
It is an app that helps me manage and pay for the supplies I use in my fields. It also helps me generate a monthly cost report.
A MUST HAVE to keep track of all products you have applied to your fields. Will drive your manpower and cost lower.