Do you find yourself making better use of your time, or do you substitute one time waster with another? I can definitely see how this would help me be more productive during my work hours though...

That's usually where those things fail for me. Still, I don't really consider them worthless - the goal is not to prevent you from wasting your time, but to make you aware you're wasting your time and turning a muscle memory action into something you actually have to think about.

In my experience phisical separation is the best for when you don't want to use your phone (for example, when going to bed or if you want to focus on discussions when having lunch) but that is not always possible - then apps like one sec or other tricks like setting your phone to gray scale, moving icons around, focus mode, screen time... All serve to nudge your brain into thinking if you really want to waste time.

For making better use of your time... Eh. Everyone struggles differently of course, but I'm unlikely to go out and run, or do focus work, when I would waste 30 minutes scrolling through Instagram. But if you make sure to have better alternatives (reading a curated feed, listening to a audiobook/podcast) then they can nudge you that way. Finding a better alternative is entirely up to you. I do find that writing down things you want to do, no matter how silly it sounds ("of course I want to read more books!") helps, especially as you can always reference to that list later when you're bored.

Second data point. I love that app. Well worth all the money.

I've also customised the automations so I have added friction to opening, for example, Slack after 6PM or on weekends. However it opens immediately during working hours.

Can vouch that this has worked for me as well with Instagram. Just hope one day they would give you the option to remove the "Explore" page. Same with YouTube shorts.

>Same with YouTube shorts.

You can use the website instead of the app, which lets you block them using extensions.