In France, I used to use Grenouille to monitor my bandwidth capacity over time. It's free but it used to under-assess my bandwidth when I was using it a few years ago. Furthermore both the website and software are in French only, and the application is restricted to French ISP.
So, what are some good applications to monitor my bandwidth capacity over time? I'm interested in applications for any OS (Win/Mac/Linux/Android/iPhone, but mostly interested in Windows right now). Basically it would do a speedtest every X minutes (+ ideally a pingtest), but I don't want to have anything to script/cron myself (or as little as possible).