I just left mine plugged into the headphone connector on the headphones. I briefly considered keeping a rubber band on them to tie to adapter to on the rare occasions when I needed to plug it into something else, but it wasn't actually a big issue for me.

Alternatively, they also have bluetooth transmitters that plug into the jack on your headphones now that you can use. But I don't know what the battery life of UI convenience is on those. I switched to the Beats X for listening on my iPhone and have never been happier. The occasional frustration of not charging my headphones pales in comparison to the everyday frustrations of untangling wires all the time.

Why don't you just get a set of headphones (https://www.sony.com/electronics/headband-headphones/mdr-1ad...) with a lightning connector and a built in DAC?

Maybe they don't want to spend $400 for specialty headphones that pretty much only work with the iPhone.

Because wireless headphones work with all BT devices and cost hundreds of dollars less.

They are also convenient to use while commuting and while working out, which is basically 95% of my time using headphones with my phone. Ambient noise while walking, riding a bus, or being in a gym is generally too noisy to prioritize audio fidelity anyway. That's not what listening to music on my portable phone is for. I have better headphones for my desk.

Disclaimer: I do not own, or use, i Devices, and refuse to buy any laptop > 700€, or phone > 250€.

I personally use my Sennheiser headphones on the PC, but also on the phone, and elsewhere. I got them from my parents when I was young, and, just like my parents used their top-of-the-line sennheiser headphones their entire life, I plan on using mine for the next 60 years, and I’ve got one single set of them.

So leaving an adapter plugged in isn’t optimal, nor is buying new headphones. Because, who are we kidding, in 60 years lightning and USB will be long gone, but 3.5mm Klincke will still exist.

It's not even that it's easy to forget, it's that it's annoying. More bulk in my pocket, and now if I want to switch from my phone to my computer I've got to unplug two things instead of one.

No, I don't consider bluetooth to be a great solution, either. I've got more than enough individual things to worry about keeping charged already. It's like the electrical outlet is trying to give birth to a damn squid every evening.