The author lists everything his phone has replaced, and the two items his phone cannot replace yet. One of those is a radar detector. To that I offer the Waze app. While it is not exactly a radar detector, it still serves the same purpose.
Funny story. I first heard of the Waze app while reading a Car & Driver magazine in my doctor's office nearly 15 years ago (possibly before 2010). There was an article on illegal cross-country car racing. One of the drivers said something like, "I use a combination of radar detector and Waze to avoid the police."
I had no idea what Waze was, and researched it as soon as I got home. It has always been crowd-sourced, and there were not many users back in those days (at least in my area), but I used it and spread the word anyway,
Those are two different use cases for me. A radar detector is much more specific. Waze replaces the usefulness of other drivers flashing their lights at me.
Anecdotally, people rarely seem to do that today for whatever reason. I expect at this point people think I'm either trying to cuss them out or complain about how bright their headlights are today, but if you see me flashing my lights there is a cop ahead looking for tickets.