I think google calender is quite overlooked here, I got a chromecast thingy and certain tasks are repetitive and you can put reminders in for anything from meetings, to food, break etc etc. it's like having a personal assistant who talks and reminds you of stuff. seems like very sweet when still in bed waking up and asking like "google, what's on the agenda today"then it tells you what your schedule is for that day, and then reminds you again when the next event is upcoming and you put those events for yourself in google calender... syncs across all devices etc.
I use this because I really tend to loose the time and end up spending more time on a particular task than intended... especially now I need it more than ever because I would start with some study work, then programming, then work, then gaming and in between there has to be rest time, lunch, rest etc... so I need that extra poke from some program or device to let me know... dude stop with this... and grab some food before you pass out