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You've lost more because the larger the disk the more space is lost in the eve whole 1000-1024 marketing thing. See the link I posted above.
Again, that's not it.

16 GB ~= 14.9 GiB
64 GB ~= 59.6 GiB
128 GB ~= 119.2 GiB

Even after you take into account the space used by iOS and pre-installed apps, unavailable capacity not accessible to the user still increases as you go up in size. Space that's just way too large to be accounted for by file system overhead.

And frankly, that answer is rubbish and I am surprised more people haven't called them out for it.

Pre-installed apps use a different block of memory than the one used to install the core os. Apps like iWork's will not count towards the space used that reduces the storage to 59 gb, so that can't be the reason.
Thanks. I think only the OP, terraphantm and you get it. :p

Another 6+ 128GB owner said his reports 114GB capacity. My 6+ 64GB reports 55.7GB.

119.2 actual storage - 114 reported capacity = 5.2 GB
59.6 actual storage - 55.7 reported capacity = 3.9 GB

5.2 - 3.9 GB = 1.3 GB

Can't use the same pre-installed apps excuse here given they have all the same apps. :rolleyes:

I checked some jailbreak discussion and it looks like terraphantm's correct. The storage in iOS devices is partitioned into a root and media partition. The root partition is where iOS firmware goes and the size of this partition varies based on the storage capacity of the device. The media partition is the one visible to users and the size of this partition is the one that gets reported in Settings - General - About - Capacity.
 
I checked some jailbreak discussion and it looks like terraphantm's correct. The storage in iOS devices is partitioned into a root and media partition. The root partition is where iOS firmware goes and the size of this partition varies based on the storage capacity of the device. The media partition is the one visible to users and the size of this partition is the one that gets reported in Settings - General - About - Capacity.

Was any of that discussion about possible reasons why apple does that, with the varying sizes?

I've erased all content and settings on my 32GB 5S with iOS 8.0.2, and reported capacity is 26.8.
It also has 608mb used from the start - I didn't restore from backup, and didn't sign into iCloud or set anything else up that would put data on the device.
That 608mb is probably partly made up of the apps that are now installed by default, that weren't on iOS 7 - podcasts, iBooks.
I've attached screenshots to show the storage screen, and that there's nothing on the iPhone yet.
 

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Was any of that discussion about possible reasons why apple does that, with the varying sizes?

Not sure. It could just be that they coded the installer to set some percentage of the total space as the root partition, and Apple never bothered fixing the value since no one complained. I can't really think of any benefits of having a larger root partition, except perhaps for certain jailbreak things.
 
Not sure. It could just be that they coded the installer to set some percentage of the total space as the root partition, and Apple never bothered fixing the value since no one complained. I can't really think of any benefits of having a larger root partition, except perhaps for certain jailbreak things.

I think some jailbreak tools allowed root partition to be resized anyway. Small benefit of jailbreaking, claiming some space back, I guess.
 
The "stolen" storage is made slightly worse by the 4.98gb of "other" I currently have showing when I connect to iTunes, with it giving no indication about what it's made up of :mad:

edit:
It went up after syncing some more stuff.
Then did another sync and it's mostly gone :-D back down to 900mb. So, ignore this post, I guess.
 
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I don't understand the confusion here... 55GB sounds right to me. 64GB is going to format to about 59.4GB. That makes iOS 8 4.4GB. This is pretty consistent with the 128GB models. 128GB will format to about 118.8GB. People are reporting about 114GB on a fresh install which makes iOS 8 4.8GB.
 
I don't understand the confusion here... 55GB sounds right to me. 64GB is going to format to about 59.4GB. That makes iOS 8 4.4GB. This is pretty consistent with the 128GB models. 128GB will format to about 118.8GB. People are reporting about 114GB on a fresh install which makes iOS 8 4.8GB.
Please see the following calculations:
16 GB ~= 14.9 GiB
64 GB ~= 59.6 GiB
128 GB ~= 119.2 GiB

128GB: 119.2 actual storage - 114 reported capacity = 5.2 GiB
64GB: 59.6 actual storage - 55.7 reported capacity = 3.9 GiB

5.2 - 3.9 GB = 1.3 GB
Why does the iOS partition use 2.4 GiB on a 16GB iPhone, 3.9 GiB on 64GB and 5.2 GiB on 128GB? What's all that extra space used for? Also, when I keep getting out of memory messages when updating apps even on a 128GB iPad, then yes, I think I can be picky about where that 1.3-2.8 GiB is going as well as the 2+ GiB worth of "Other". 1.3-2.8 GiB is a lot of space to be just file system overhead. :rolleyes:
 
Here's a question... is there a possible answer that people will be satisfied with? Regardless why, it's how it is, always has been, and shows no sign of changing. I am all about discussion, but the dead horse has been beaten a bit. JMO.
 
Please see the following calculations:

Why does the iOS partition use 2.4 GiB on a 16GB iPhone, 3.9 GiB on 64GB and 5.2 GiB on 128GB? What's all that extra space used for? Also, when I keep getting out of memory messages when updating apps even on a 128GB iPad, then yes, I think I can be picky about where that 1.3-2.8 GiB is going as well as the 2+ GiB worth of "Other". 1.3-2.8 GiB is a lot of space to be just file system overhead. :rolleyes:

Why are you assuming the differences are because of iOS? Likely the differences are in the formatting. Just look at SDDs, the usable space varies a lot between manufactures because of reserved space and other variables.

At the end of the day why does it matter? Do you really think Apple is withholding space just to piss people off?
 
It is because storage drive capacity is calculated...

[...]

...now add the OS and you are down to your 55GB.

This has been the most intelligent post I've seen in a long time in this section of MacRumors.

Also, for those wondering, why the math still doesn't add up. Every OS formats drives differently (FAT, FAT32, NTFS, OS Journales... etc) the type of formatting will affect drive capacity as well.

Also, no drives or flash modules are exact, your iPhone's flash module may be for instance 62,330,000,000 bytes while some one else's might be 63,500,300,000 bytes. Those differences are also to be taken into account. If you really need to know, this is due to the manufacturing techniques and how the chip ended up being made.
 
Here's a question... is there a possible answer that people will be satisfied with? Regardless why, it's how it is, always has been, and shows no sign of changing. I am all about discussion, but the dead horse has been beaten a bit. JMO.
I think we've pretty much agreed on the explanation being the root partition size varying depending on device storage. What for? Unless I jailbreak or at least research the issue further, I wouldn't really know. Google's not being much help so I reckon I'd probably need to read some enthusiast or dev discussions in XDA forums or something to actually learn why.

However, if someone's going to post with an excuse that doesn't really explain the actual issue under discussion (yes, we already know that 1 GiB = 2^30 bytes and that's actually factored in to my calculations), then yes, I'm going to continue replying. If someone doesn't actually know the reason and will just be regurgitating the same excuses (decimal-binary conversion, pre-installed apps, etc) that's already been covered from page 1 of this thread, then they can just opt not to reply to this thread. :rolleyes:
 
Why are you assuming the differences are because of iOS? Likely the differences are in the formatting. Just look at SDDs, the usable space varies a lot between manufactures because of reserved space and other variables.

At the end of the day why does it matter? Do you really think Apple is withholding space just to piss people off?
Withholding space to piss people off? No, I don't think so. However, what's wrong with wanting to know how the space is used (whether it be cache, overprovisioning, empty space, etc)? Heck, if a bigger capacity iDevice leads to better performance due to having more cache, then I'd like to know.

As for SSDs, I own several SSDs (Intel, OCZ, SanDisk, Samsung, Crucial, etc) and capacities on those is pretty much what's stated on the box (accounting for the 7.3% disparity between GB and GiB). Doesn't really matter what brand. There migh be a few megabytes difference but nothing drastic.

120GB: ~112GiB
128GB: ~119GiB
240GB: ~224GiB
256GB: ~238GiB
1TB: ~931GiB

This has been the most intelligent post I've seen in a long time in this section of MacRumors.

Also, for those wondering, why the math still doesn't add up. Every OS formats drives differently (FAT, FAT32, NTFS, OS Journales... etc) the type of formatting will affect drive capacity as well.

Also, no drives or flash modules are exact, your iPhone's flash module may be for instance 62,330,000,000 bytes while some one else's might be 63,500,300,000 bytes. Those differences are also to be taken into account. If you really need to know, this is due to the manufacturing techniques and how the chip ended up being made.
And again, file system (FAT, FAT32, NTFS, HFS, ext3, etc) overhead isn't that huge for a mere difference of 48-112GB. As for flash modules not being exact, NAND flash is available in powers of two. That means a 128GB iPad does have 128GiB in NAND flash. There might be bad blocks, sure, but there's a 7.3% disparity between GB and GiB to be used as spare area for garbage collection, wear levelling, bad block replacement, etc. Otherwise, it's possible to reach a scenario where flash memory is unresponsive.
 
But my question was, is that answer good enough. Now that people know this, do they feel better about their missing space?
I learned from terraphantm's post that the reason for this is most likely the size of the root partition which lead to the correct "research parameters". I also learned that if I jailbreak (granted not available yet for iOS 8), I can reduce the size of the root partition so I have more space for my media. From that, I also learned it was possible to have a pagefile on the drive (stored on the root partition) to minimize those pesky Safari tab refreshes. I'd say for me, yes it was a productive discussion. :)
 
The 64GB versions come out of the box with GarageBand, iMovie, Keynote, Numbers, Pages etc all large apps, all preinstalled. But also deletable.

edit: just checked through all. Their app store compressed archive size before install is 2.1GB. Could easily expand to 4GB when decompressed + any content from music/video that didn't make it back through the restore process.

I bought a 64GB iPhone 6+ and my phone doesn't come with any of the apps you listed. When I check the App Store both on iTunes and on my device's App Store app itself, apps such as Numbers show a price tag of $9.99. How do I get the free apps?

I bought my phone full-priced from AT&T btw.
 
This has been the most intelligent post I've seen in a long time in this section of MacRumors.

Also, for those wondering, why the math still doesn't add up. Every OS formats drives differently (FAT, FAT32, NTFS, OS Journales... etc) the type of formatting will affect drive capacity as well.

Also, no drives or flash modules are exact, your iPhone's flash module may be for instance 62,330,000,000 bytes while some one else's might be 63,500,300,000 bytes. Those differences are also to be taken into account. If you really need to know, this is due to the manufacturing techniques and how the chip ended up being made.

Formatting itself won't ever take more than a couple hundred megs (if you count things like the EFI partition as a formatting loss). Vast majority of the time it's a few K. Significant when talking about floppy disks, insignificant otherwise.

The values aren't exact, but typically they're close. I've never come across a hard drive that was off by more than 1%

As discussed above, the discrepancy is very likely due to the root partition.
 
Formatting itself won't ever take more than a couple hundred megs (if you count things like the EFI partition as a formatting loss). Vast majority of the time it's a few K. Significant when talking about floppy disks, insignificant otherwise.

The values aren't exact, but typically they're close. I've never come across a hard drive that was off by more than 1%

As discussed above, the discrepancy is very likely due to the root partition.


Root can be one cause. Back in 1.x days, the root partition itself was a whopping 750MB of the 8GB an iPhone had. Now a days, considering the newer OS, root might be itself 1GB minimum.

And again, file system (FAT, FAT32, NTFS, HFS, ext3, etc) overhead isn't that huge for a mere difference of 48-112GB. As for flash modules not being exact, NAND flash is available in powers of two. That means a 128GB iPad does have 128GiB in NAND flash. There might be bad blocks, sure, but there's a 7.3% disparity between GB and GiB to be used as spare area for garbage collection, wear levelling, bad block replacement, etc. Otherwise, it's possible to reach a scenario where flash memory is unresponsive.

Not quite... the difference is Apple's vs Microsoft's method of counting. In OS X, you get the actual byte count (which is why we get 250GB as 250GB). In Windows, we still get base 2 byte count [ie 250GB looks as 232GB]. Some people don't know this and hence may think "Oh, my iPhone has less than advertised".

Normally (as you mention as well) it is always the case that in an SSD, when they sell you a 128GB (for instance) drive, that drive is actually around 136GB. That extra 8GB as you so eloquently stated is used for overhead, wear leveling, replacement and TRIM. However, in the case of the iPhone we don't have additional NAND modules. Hence this theory is out the window.

What I think is what the other poster I quoted is happening. The root partition has grown. Yes type of file system doesn't account for much, but it is a factor in determining that extra (or not) GB. Flash drives are not exact. They have small variations. There is no perfect NAND flash module, it simply can't be made. You either have more or less, but on average you get what you pay for.
 
The answer is we may never know unless one of the Apple engineers who designed the current file system sees this thread and decides to answer. Crossing my fingers :p
 
Normally (as you mention as well) it is always the case that in an SSD, when they sell you a 128GB (for instance) drive, that drive is actually around 136GB. That extra 8GB as you so eloquently stated is used for overhead, wear leveling, replacement and TRIM. However, in the case of the iPhone we don't have additional NAND modules. Hence this theory is out the window.
They're not additional NAND modules. Given the way NAND stores data, capacity is in powers of 2 much like RAM. Now unless Apple has been manufacturing their own NAND which somehow stores bits differently, a 128 GB iDevice does contain 128 GiB (or 137,438,953,472 give or take a few megabytes due to bad blocks) of flash storage (in terms of chips). Now since I assume Apple is using self-contained eMMC, only 128 GB (or 128,000,000,000 give or take a few bytes) is available to Apple right off the bat. I've never claimed Apple is shipping iPads with less flash storage than advertised. I just questioned allocation of those bytes.

By the way, I read before that on iOS, GB stands for binary GB or 2^30 bytes. I don't want to search for the Apple KB article since I'm on an iPad and wouldn't want Safari to refresh this tab and lose the entire post. :rolleyes:

What I think is what the other poster I quoted is happening. The root partition has grown. Yes type of file system doesn't account for much, but it is a factor in determining that extra (or not) GB. Flash drives are not exact. They have small variations. There is no perfect NAND flash module, it simply can't be made. You either have more or less, but on average you get what you pay for.
Yes, we've already pretty much come to the conclusion that the size of the root partition varies based on storage capacity.

By the way, I reckon if you check a whole bunch of iPhones of the same model and storage running the same firmware version, you'd find reported capacity is the same for all of them. I know it's not exhaustive but I've found reported capacity to be the same within the same device model and firmware version for various Apple products I own. Sure, there's no perfect NAND flash but factory bad blocks are usually hidden in the 7.3% GB-GiB difference. And really, Apple isn't paying for individual NAND modules. They're paying for essentially a complete SSD already.

Mind, crappy NAND flash probably get sold and used for flash drives, etc. The ones used in SSDs and tablets are relatively high quality. I remember reading an article a couple of years ago from a custom flash drive manufacturer saying NAND manufacturers have all moved to making 8 GiB dies minimum. If there's only a few % bad blocks, it's made into an 8 GB flash drive. If the bad blocks reach a certain threshold, then more blocks are disabled and it's sold as 4 GB. If there are even more bad blocks for 4 GB, then even more blocks are disabled and it's sold as 2 GB. ;)

By the way, just ran storage benchmarks using PerformanceTest Mobile on my 6 Plus 64GB. Sequential read 191 MB/s, sequential write 56.9 MB/s. Seems like USB3 would help speed up iTunes backups. :)
 
By the way, just ran storage benchmarks using PerformanceTest Mobile on my 6 Plus 64GB. Sequential read 191 MB/s, sequential write 56.9 MB/s. Seems like USB3 would help speed up iTunes backups. :)

Interesting. I wonder if iTunes wifi sync would actually be faster than USB (on an 802.11ac network)
 
Interesting. I wonder if iTunes wifi sync would actually be faster than USB (on an 802.11ac network)
Network conditions would probably have to be pretty perfect for that to happen. Real-world throughput of USB 2.0 maxes out at 40 MB/s which is 320 Mbps. From SmallNetBuilder, while AC1900 can reach max throughput of ~500 Mbps, average sustained is just ~200 Mbps. What's max AC link speed of the iPhone 6, anyway?
 
I bought a 64GB iPhone 6+ and my phone doesn't come with any of the apps you listed. When I check the App Store both on iTunes and on my device's App Store app itself, apps such as Numbers show a price tag of $9.99. How do I get the free apps?

I bought my phone full-priced from AT&T btw.

Call Applecare, something erred.
 
Is its true that higher capacity models (64GB) compared to 16GB perform smoother and faster due to the increased storage? Is this proven?
 
128 GB ~= 119.2 GiB


Where did this number come from, I may have missed it.

My 128GB IP6, Its seem to missing 4.2GB after taking out used storage of 3.8.
I know there is a percentage of unusable space. It seems 4 gigs is excessive. Trust me I was very frugal of my storage space with my IP5 16GB. So after auditing myself for usage. I'm just saying wheres that 4.2GB.
 
Where did this number come from, I may have missed it.

My 128GB IP6, Its seem to missing 4.2GB after taking out used storage of 3.8.
I know there is a percentage of unusable space. It seems 4 gigs is excessive. Trust me I was very frugal of my storage space with my IP5 16GB. So after auditing myself for usage. I'm just saying wheres that 4.2GB.
1 GiB = 2^30 Bytes = 1,073,741,824 Bytes

128,000,000,000 Bytes / 1,073,741,824 Bytes/GiB = 119.2 GiB

If you go to Settings - General - About, you'll probably find Capacity is ~114GB (at least that's the number reported by 6 Plus users).

Assuming you're talking about the difference between Capacity and expected storage, we're guessing it because of a bigger root partition (where system files, cache, etc are stored).

Estimated root partition sizes for various capacities (iPhone 6/6+):
16GB: 2.4 GiB
64GB: 3.9 GiB
128GB: 5.2 GiB

Now if you meant "Other" storage, it could be cached mail, messages, old app data, etc.
 
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