Instruction: Generate an answer to the question by utilizing the information contained in the document.

Input:
Question: Will this adapter work in an iPhone 4S?  My other 3.5 mm plugs do not work in my iphone because of Apple's desire to keep it Apple.
Document: This adapter does what it needs to do: Break out the 3.5&#34; mic and headphone plugs from cell phone 4-pin ports (in this case, an iPhone). 1 star off since it doesn't feel like the sturdiest or most long-term-durable, but, still, great.
I wanted to plug in my laptop and blackberry a headset with mic with two plugs so I can make phone calls; the laptop, as well as the blackberry, has only a 3.5 mm jack. And it worked great! I haven't noticed any loss in volume as others mentioned.
Does NOT work on all my Apple Devices.-- Did work  on Macbook Air but one lapel mic had severe hum and another had a very low volume level.-- DID NOT work on iPhone 4S at all- strange-- Did work on iPad mini 1st generation but also with bad results.The hum was obviously a function of the impedance of the mic not matching that of the MBA or iPad so not really to blamed on the cable.
I don't know whether it's the adapter itself, or simply that Apple did something differently with the 4-pole 3.5 input on the iPod Touch 5, but either way it's a no-go.
I bought this splitter to work in conjunction with an external mic I bought for my computer. The mic didn't work when I plugged it directly into my computer's 3.5 mm headphone jack, but when I plugged the mic into the mic jack of this splitter and then plugged the other end of the splitter into the headphone jack of my computer, the mic worked just fine.
This is more of an annoyance, as I can always find a stable position for the cable to keep producing stereo sound. To my knowledge, the right channel and the microphone consistently work fine.I would say that this cable deserves 3.5 out of 5, but I rounded up because I really like the cable. Most cables will deteriorate after being in a car going from a 32F freezing at night to as high as 120F during the day in sunlight.
I bought this to use with a MacBook Pro Retina to get audio in. Well, it turns out Apple doesn't let you do that. I assume it would work with an actual headset with programs that support it, and almost definitely would work with an iPhone, etc. Build quality is excellent and the plugs are no bigger than they need to be meaning it should fit devices with a recessed headphone jack.
I was unable to record audio with this adapter on my iPhone 4/4S or Samsung Galaxy S 2. This adapter apparently has the contact points reversed for smartphones.The "Headset Buddy: PC Headset to 3.5mm Smartphone Adapter: Convert Dual 3.5mm to 3.5mm, PC Computer Headset to iPhone, Blackberry, Droid, Palm, Samsung, LG, HTC" adapters for recording audio from an external microphone or line in.
I have tried this item in my MacBook and iPhone.Pros:- Thin outer layering of Plastic so it doesn't interfere with your iPhone case- Durable material (very strong and quality plastic)Cons:- Microphone and Volume controls on Apple earbuds don't work (even though it is a 3 pin connector)- Doesn't work in some versions of Apple ComputersStarTech is generally a good, quality brand. I haven't had any problems with their products in the past. I would recommend this brand, but NOT this product.
My Samsung Galaxy Note has some issues with 3.5 mm audio socket when I plug regular earphones in, but through those (even when I don't need microphone) most of them are gone.
Answer: This particular item will not split the iPhone headphone jack into mic and headphone entities. Apple uses a specific version of trrs (4 conductor configuration) conforming to the CTIA standard. apple and HTC are the major players that use this.  Others, like Samsung and Nokia, use the more common OMTP configuration. While the plugs look identical, the configuration is distinctly dissimilar. The CTIA configure has the mic signal based on the sleeve; versus the OMTP use of the second ring for the mic signal. So. If you use THIS cable with an apple product (iPhone, iPod, iPad, macbookpro/air), once connected, only the headphone feature will work via the splitter.  Short answer...NO. This cable will not work properly on an apple device.  (Edit. Correction. Newer samsung devices use the same CTIA configuration.)