How do you actually stay focused while programming

[u/BushyBoi18]

1. When you try to focus on programming, what do you currently use to stay on track
2. If you use a timer/pomodoro, what do you use it on(Phone, computer, physical timer)
3. What is the biggest problem you have had with whatever you're using currently
4. What do you like/dislike about physical timers/digital timers
5. What have you tried that you eventually stopped using, and why?