
iOS 9 space-saving “app slicing” disabled for now, will return in future update - cpeterso
http://arstechnica.com/apple/2015/09/ios-9s-space-saving-app-slicing-disabled-for-now-will-return-in-future-update/
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kalleboo
Interesting that iCloud backups actually upload the apps from your device
rather than just noting "you had XXX app version XXX" and redownloading it
from the App Store on restore.

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lpsz
Updating iOS via iTunes (for beta installs, restores, etc.) has the quirk of
syncing apps to iTunes, and then syncing them back to the phone. This seems
like a legacy annoying thing to me: why can't it just transparently re-
download them? In fact, the new iOS 9 upgrade has the "delete and then re-
download apps" feature for those with insufficient space for upgrade. Not to
mention, there's the "purchased" tab on your device. So, this _is_ possible!

Going further, even the prompt to "delete and then re-download apps due to
insufficient space for OS upgrade" seems unnecessary, as if revealing an
unimportant implementation detail. Why can't it just automatically do the
right thing? I won't mind if the app is missing from my iPhone for a couple of
minutes. If the reason is bandwidth, perhaps it could say "we'll do this on
wi-fi only."

Similarly, I wish purchased iTunes media started working the "streaming" way,
too. I don't want the TV show to take up Gbs of disk space, don't particularly
care for the physical file present on my disk. Could still have an opt-in "use
offline" option for those who need it.

Or are these all issues to appease people who want to feel like they "own"
content (apps, media, etc.)?

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tammer
I think this is a great forward-thinking feature of iOS. Some apps I have are
no longer available via the app store. The only way I can retain access to
them is via local copies.

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LeoNatan25
That's not true. You can access the last version of any purchased app from the
AppStore -> Updates -> Purchased, regardless if it is available or not on the
store for you.

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TetOn
Tammer has the right of it, actually. There are (at least) two classes of "not
on the app store," the first is as you describe, not generally available but
there for legacy purposes and can be re-downloaded from the Purchased (not on
this device) tab. The second is completely gone and only available if you've
backed them up somewhere. There's even a modal dialogue alerting you to this
fact when you have finished a restore (basically: go sync if you want certain
apps that could not be downloaded back)

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LeoNatan25
Unless an app has been completely removed from the AppStore by Apple (for
instance, a malware app), the last available version of all apps will exist in
the "Purchased" list. If an app is "completely gone", it probably has a good
reason not to be there in the vast majority of cases.

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untog
The owner can remove it, too. Marco Arment's iOS ad blocker is the most
immediate example that comes to mind.

 _If an app is "completely gone", it probably has a good reason not to be
there in the vast majority of cases._

Cold comfort to those who paid for said app.

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LeoNatan25
Are you sure Arment's app does not appear in the "Purchased" history list? As
I remember, unless you request a refund, it will appear there.

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nmcfarl
I have an app that I love whose owner went out of business after removing the
app from the store. I purchased it for my 3G,and since then I've had to
manually transfer it from iTunes, until I switched to iCloud backups which
have muddled the issue for me... Anyhow it shows up in "purchased" with an
"open" button if it's on the device, and (my recollection is that it) just
shows up with no button and no download icon if it is not.

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tobias3
So, if I enable bitcode it just doubles the size of my binaries currently?

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simonh
It (roughly) doubles the size of the app bundle you upload to Apple. They then
compile that down to create normal sized binaries, which are what are actually
downloaded to the device.

Bear in mind the source->bitcode->binary process (I'm simplifying here) was
previously all performed by LLVM on your computer anyway. It's just that now
the final bitcode->binary step is done by Apple, to allow device-specific
optimizations of the binary for the devices that are downloading it without
you having to do all those device specific optimized builds yourself.

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ksk
Do you know what the performance increase is of these optimized builds?

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simonh
No idea. We'd need to do on-device profiling of 'plain' builds directly from
XCode alongside the builds downloaded from the app store, but of course
optimizations may only be possible on particular devices, and some apps would
benefit more than others, so you'd have to do a huge amount of testing to
track down the differences. Also Apple may be doing this due to planned
advantages in the future, so testing done now might be pointless anyway.

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ksk
Its just strange that Apple has not presented any actual numbers on this.
Usually you'd expect them to talk about how XYZ is 90% faster, and 100x
awesome and what not. It makes me think that they have something else in mind.

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Glide
It's most likely so you don't have to update the binary when the next version
of LLVM comes out. There are a lot of apps that don't get updated with major
iOS versions and they would likely see improvement.

Conspiracy theories aside, wouldn't it take them more effort to ship a
different version of LLVM for Xcode and another one that runs against bitcode?

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ksk
It is not a conspiracy theory per se, I'm just skeptical of their optimization
claims. In theory, sure. In practice, I'd have to see hard data.

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rsl7
Too bad. This was going to make the 16G iPhone actually viable.

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caio1982
I'm running the latest iOS released this week on my 4G iPhone 4S, 1.7G still
free. Granted, I don't store videos/photos (long term) that much.

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omni
The storage problems are exacerbated for the newer phones, largely because the
cameras keep taking higher resolution pictures.

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venomsnake
I have an even better space saving feature for iOS devices - quadruple the
storage. The flash storage prices have always been the biggest ripoff of iOS.
And the increases of storage on the devices have not kept with the way the
capacity have increased and prices have gone down.

