I use Google sheets. Helps me keep track of jobs, dates, locations, payments, payment dates, miles traveled, expenses, etc. I use one sheet for each calendar month. Once the month is paid, I change the tab color of the sheet to green and hide the sheet, so I know at a glance that it's done. Then I have a formula that consolidates all data from 12 sheets into one, which I use to do various pivot tables. That helps me keep track of earnings per month, per company, etc. and also has all the information I need to do my taxes at the end of the year.
I find Google sheets to be very flexible. Also access via internet is important to me so I can update the document from anywhere.