Welcome to your Throne
Los Angeles Metro has begun placing portable, self-contained bathrooms near many light rail stations. They are developed by a company called "Throne." In fact, a photo of the Throne at downtown Santa Monica's E line station graces the top of Throne's website.
This company calls its product:
The smart, delightful public restroom
Here's the one I used, in South Pasadena:


The main thing about Throne bathrooms is that you need a phone or a "Throne tap card" to access them. This prevents people from using the bathroom anonymously, but also prevents people who don't have phones from using them. Before continuing, I'd like to just say that I think big cities like Los Angeles should have robust public bathroom systems that are truly free to enter. The main reason bathrooms like Throne even exist is because the state is too afraid of maintaining and enforcing "normal" bathroom usage as a part of its own slate of public services... and the reason they're probably afraid of doing this is because the state has refused to house all its residents. So!!! There's that. (More on this at the end.)
The other thing about Thrones is that the door just pops open after 10 minutes. It will flash lights at you if you're about to be suddenly exposed... I felt like it would be rude to test this out, so I didn't.

All the places in the bathroom where you would expect to have to press a button are instead no-touch motion sensors. So you activate the sink with a motion sensor, flush with a motion sensor, exit by opening the door with a sensor, etc.


It smelled completely neutral to me! The ceiling has a very robust fan assembly which I assume is used for airing out the bathroom cabin. There are apparently staff who also clean the bathroom.
If you check out their website, a lot of this company's tech innovations are essentially time-saving cleaning techniques. The mirror has a film on it which can be peeled off to remove graffiti; the walls are covered in an abstract, overlapping leaf pattern, and if someone graffitis the walls, they just stick another leaf over it and cover it up.
Using the system required me to scan a QR code on the door. It populated my iMessage app with a number and the phrase "Send this message to use the South Pasadena Throne." I did, and the door opened.
Throne's website addresses the complaint that a phone-based lock is unfair, but its response is:
Fun fact: 98% of Americans own some kind of cell phone (according to Pew Research Center). These folks can scan the QR code or text the number on the Throne to enter. For those who don’t have a phone, Throne tap cards can be provided to local libraries, homeless service providers, and other advocacy groups for distribution.
Basically, the process of using this bathroom is meant to apply just enough friction to prevent completely destitute people living on the street without phones or without contacts in social services from using it. I think a clean, private bathroom means a lot for many people, and I'm glad this exists. But I'm also left thinking about how this entire system deliberately avoids solving the main shocked complaint anyone makes about our housing crisis in California - that if you are out and about in certain places, including near Metro stations, you may see someone relieve themselves in the street.
I left the Throne thinking about how essential it is that Los Angeles create some kind of public bathroom system and staff it with humans. American cities are absolutely addicted to solving problems only with the use of startups, private partnerships, weird tech, or gimmick services... we almost never choose the most robust and long-lasting solution to any problem.
South Korea has a robust system of public bathrooms - apparently some of the ones in subway stations require transit cards to enter, but others don't. I have heard that the ubiquity of these bathrooms makes navigating society with Crohn's, or an elderly relative, much easier. If we're thinking about what we'd want for "the Los Angeles Mamdani's" mythical future platform, I think I'd like "fully staffed bathrooms" on the list somewhere. There's absolutely no reason why we should be relying on something like "a startup for bathrooms" to solve this problem when we could solve it ourselves. If anything, the reason we don't solve these problems ourselves is probably just that it would add headcount to the city.
I think the big lesson many cities should be taking from Mamdani's campaign is that loads of voters are not afraid of supporting complex, intimidating, high-headcount public services. People just want nice things. A clean bathroom is nice! If you staff it correctly, we could have one!! Pretending like we can't have one is asinine!