Instruction: Answer the given question by extracting information from the supporting document.

Input:
Question: a) Does anyone have an iPhone 4 and/or iPad mini that this works with? and b) If I get the USB receiver that Amazon suggests, will it work on a PC?
Document: The sound quality lowers when the mic is accessed on a PC. works fine on iPod Touch, iPad 2, and iPhone 4. just not on windows and/or mac os x.
They cost about $30 AUD. & they work very well with anything that can take a USB transmitter (no software required). I've had them plug & play in PC/Mac/Linux.Amazon should stock these- they work well & take AAA's (I use rechargeable)instead of a non-replaceable rechargeable. Amazon? Are you "listening"? :)
TRASH, TRASH AND TRASH. Does not work with iPhone 4. Barely works with an iPad 1. Connects, stays connected, loses connection. Works on and off, then works, then does not, constantly trying to reconnect. Tried to return 36 days later and now I cannot. HORRIBLE.
I had to work with Logitech Tech Support to find out why this headset is not working with the USB - Bluetooth Dongle (adapter) that Amazon is trying to bundle with this item, to find out that this particular Logitech Bluetooth Headset is only compatible with "native" bluetooth, meaning built-in, like in a cell phone, ipad, laptop, etc.
So, I went to settings on my iPad, clicked on general and followed the steps for syncing with the new headset. To my surprise it worked the first time. Very easy. If I can do it, anyone can. My six year old grandson likes them too, and he is very picky with earbuds and headsets. I just needed to get a USB adapter to charge the headset. Nice product Logitech.
...I mean, what do you expect for sound in a headset/mic of this cost?The sound is thin & anaemic. The microphone works well enough to use it with Skype. Supposedly, sound quality is better when paired with the iphone/pad. If I get a chance to test it with one of those items, I'll return to update this review.I've used it with a PC & an iMac running Snow Leopard.
I recommend this phone because It connects with every product that use bluetooth. I tested in the PC with adapter, Notebook,  iPhone, iPad, Samsung Galaxy S4.The quality is good. The microphone works perfectly and hide inside the headset. Well discreet!
These wireless headphones work great with my wife's iPhone 4S. She was bugging me to get some sort of wireless headphones so she could talk on her iPhone without having to hold the phone for hours. I had a hard time finding the right ones, but these work very good, easy to sync to her iPhone. Charging is easy 2, just plug in the USB to your laptop or desktop and leave it for a few hours, easy and you have a full charge within a few hours.
I have had these for a while - I wear them almost every day while I am out walking. I love not having the wires dangling as I walk. I have paired them with my iPod, my droid phone and iPad. I could not get them to work with my PC with Bluetooth - but since that was not why I bought them I didn't try very hard. I liked them so much I bought a second pair for my daughter for use on her droid phone.
I guess it was just a deal I didn't want to pass up. These are half the price of every other bluetooth headset I've seen, so I knew it was a gamble. Looks like I'm going to have to spend a few extra dollars and get myself a wireless USB one. I think I'll try Logitech's H600. I've always loved Logitech, and these headphones are compatible with anything bluetooth, just don't expect them to be reliable like the more expensive bluetooth headsets, especially for PC users.
Answer: I have an I Phone 4 and this works well with it, the extra stuff like voice activation does not work, it just answers calls and hangs up calls, and does a mute thing also. I do not have the USB Bluetooth adapter so cannot answer that question.