I'm using two data sources. Toshl for knowing how much I'm spending (and for certain types of income), Toggl for tracking my freelancing with an attached hourly rate.

The fact that I can see my income as a daily thing and not something that happens every X weeks is really what makes this thing useful and cool because it can essentially turn each day of the month into a simple number saying whether it's a positive or negative day (and by how much).

Then it's just some playing around with rolling averages and some other stuff to get a prediction that is surprisingly good.

Is it difficult to scrape? I log my balance daily with a simple Python script that logs in and scrapes the value.