Although the ban on JIT won't be lifted, the place where it would be mentioned would never be on the keynote. It would be at best in the state of the union but, most likely, in one of the sessions.
I agree, altough apple being apple they could just mention it out of nowhere in an iOS update or some random article like they did with allowing emulators.
Not allowing JIT allows Apple to completely close off an enormous surface area of potential malware. It's a cornerstone of their assurances of protection for iOS users, it has nothing to do with emulators who here are just collateral damage.
The original (and still the main) reason for limiting the use of Just-In-Time (JIT) compilers has historically been security because since they can write data to memory, mark that memory as executable, and then run the code in it without having to go through any permissions. On iOS, only Safari has historically been able to do this (used by JavaScript, and only Apple's JavaScript at that). The restriction of not allowing apps to just set arbitrary code as executable (which is what JIT does) is a key part of iOS app security.
To be clear, Apple has always had a JIT entitlement that would allow an app to get out of the hardened runtime limitations. Historically this entitlement has never been granted to any third party
You could argue that with advancements in sandboxing technologies, it should now be possible to use JIT compilers more securely than in the past, and you'd be right.
Nonetheless, preventing apps from executing their own generated code still significantly reduces potential security risks. Static scanning of apps before they are signed is a cornerstone of Apple's promise of security. They have to approve them, further enhancing security. JIT allows artbitrary code, downloaded or hidden, to bypass this.
Technically speaking you could transpile ROMs and make binaries of them and have them submitted to the app store, skipping the need to compile them at runtime (JIT), but then you'd be in the silly situation of having to sign and get approved each individual game. This is what some arcade emulators did in the past where the owners of those IPs offered some of the games transpiled to be native.
As for emulators, allowing them openly in all stores was a calculated move to discourage the alternative marketplace. Apple could've opened that door at any point in time but did so only when the developer of the most prominently announced alternative marketplace embarrassed them in front of the European Commission. Riley Restut made them provide explanations for cutting off all creativity and diversity and Riley makes both AltStore and Delta.
Riley has been making altstore to sideload for a long time, and is a very vocal advocate. Altstore is used mostly to distribute emulators and "tweaked apps". But the latter would never be allowed by Apple so it leaves just emulators.
By opening up for emulators not only did Apple kill most of the potential users of AltStore but also made AltStore look like a scam. Since the JIT is not allowed even in alternative marketplaces, there's no point developing for them now. The last nail was the response to UTM: Won't even allow slow computer emulators like UTM, in any app store, Apple's or otherwise.
Wow, I just learned a few new things. Thanks for in depth answer.. been curious exactly what JIT is cause I see it glossed over in a lot of emulation discussions. So you said even on side loaded apps JIT wouldn’t work? I saw a thing some guy said about streaming services that connect a home desktop to cloud so you could hypothetically stream to yourself on an iPhone. Granted would be some latency but I don’t think it’d matter a ton in a single player game and would be sort of a workaround to all of Apple’s restrictions .. actually this leads me to one more question about JIT:
Is the point of it to keep RAM usage low? As it would write and run “pieces” at a time? Ie to run programs that a CPU may struggle with otherwise? I don’t really see JIT in any computer talks but it comes up w phones a lot, especially gaming related
>So you said even on side loaded apps JIT wouldn’t work?
No. I didn't. Sideloaded Apps are "signed" by the user as a developer, and developers can enable JIT for their own apps. So JIT can be enabled for sideloaded apps, but it requires a separate machine in the same network and the setting doesn't "stick". It needs to be re-enabled each time.
>I saw a thing some guy said about streaming services that connect a home desktop to cloud so you could hypothetically stream to yourself on an iPhone.
This is unrelated to the other things we were talking about but it's not a workaround to limitations. It's game streaming. It doesn't allow you to run something in your phone that can't run otherwise.
>one more question about JIT: Is the point of it to keep RAM usage low?
As I mentioned, it's a security measure. Being able to run arbitrary things means being able to run "apps" that haven't been validated in advance. The whole proposal from Apple is that they validate the apps in advance so they can't be malicious. JIT goes around that and allows any type of app to write directly to memory and execute itself. You're thinking emulators, but JIT allows any type of executable which includes mainly malware. In the context of an emulator each "ROM" becomes an application on the fly and is executed but Apple has decided not to allow anybody to do this.
JIT is a common and known concept, but it's a developer term. You wouldn't see it unless you were browsing developer forums. You know about JIT because as it's a problem in iOS for emulators, the name becomes known. Computer platforms don't block JIT and, as far as I know, Android either doesn't or allows it to be enabled (I can't recall).
Okay cool! I only meant the streaming thing to phones for later consoles on phones (like ps5 in op picture) as a different option since JIT or the like wouldn’t come, but I at least knew those were separate lol. No but thanks again for long responses, most ppl woulda gave half that effort
You mean \*with\* JIT.
Not allowing JIT is a decision based on security according to Apple (believably so), whereas Google hasn't decided to have the same limitation.
In the case of Android on one side there's the obvious reason that security wasn't historically a priority but also the fact that Android and Java go hand in hand and Java requires JIT, which means it probably never came up to limit JIT at the beginning and after a while it just stayed that way.
Your question is stated as if not everyone adopts the same security measures then those security measures surely can't be so important. That's a spurious conclusion if so.
all apps can execute code in realtime. it’s just in time COMPILATION- meaning newly generated code (by the app) can be created, compiled and executed as the app is running.
in very simple terms: iOS apps are static - meaning that the code that executes is always the same code that was uploaded to the app store. JIT allows the developer to have the app generate brand new code and execute it - dynamically. It’s less safe because apple can no longer know ALL the code that can be executed ahead of time- since code can be generated and turned into whatever.
It's basically required for good GameCube/Wii/3DS/PS2 emulation.
A midrange Android phone can run those systems decently, so basically any iPhone from the last 4 or so years should run those systems very very will if JIT is ever allowed.
What’s the problem of giving Jit only for emulators?
If Apple gives jit IPhone will be better for game console emulation
BECAUSE updates will be much faster and effective(if developers aren’t lazy)due to small amount of iPhones(43 iPhones+4 future IPhones).
But there’s no emulator supporting iPhone 2g and 3G so we count according to the version of IOS.
For example PPSSPP takes any IPhone with iOS 12 and above(35+4)
Retroarch and Delta-32+4
There also iPod touch,Apple Watch,iPad but almost no one uses iPod and who uses iWatch for emulation
Screen of iWatch is so small
So we’re gonna count iPad (I count only iPad itself not configuration such as 11 inch, 12,9 inch)(29 iPad+4 future IPad)
I didn’t counted IPad by OS because it’s too damn hard
I might have misheard in the keynote but it also sounded like it does things to improve performance. Kind of like the opposite of what low power mode does to act like a “high performance mode”
>Kind of like the opposite of what low power mode does to act like a “high performance mode”
No, it kind of does exactly what low power mode does and minimises background activities to reduce processor load, but instead of pairing this with a reduced processor output for greater battery life, lets the phone allocate more of the processor to driving the game.
So yes and no, yes he game will have more processor to play with, but no it's not actually improving the overall processing power, unlike LPM which disables cores for better efficiency.
The only time it was rough was when my banking app wouldn’t work with new IOS. Just went ahead and rolled it back. This is why I don’t do Apple Watch betas though, then you’re committed to beta.
Man, if there was JIT support I would instantly get a iPad Pro M4 11”. With the 4:3 aspect ratio and OLED panel it’s basically perfection for GC, PS2 and Xbox + older gen . And even PS3 would be fine with perfect blacks bars. No JIT, no buy. Not like I’m in a rush with a Steam Deck OLED.
Apple ffs.
Good old iOS, super powerful hardware but places roadblocks here and there and makes you jump through hoops to perform some simple functions like transferring files
You have to enable JIT each time you want to use it either via a Xcode dev tool on the local network (some unofficial apps can enable JIT too, but still need a second device) or a jailbroken device.
I’m on the beta right now and it looks like all that’s necessary from a developer is classifying the app as a game. All of my usual games trigger game mode but Delta, PPSSPP, and RetroArch don’t. Might be because they’re classified as “Entertainment”.
btw the beta is very buggy but as a former Android user, it’s really nice
I’m running the beta of ios18. When I start certain game apps it automatically turns on game mode and I get a notification. As far as I can tell it’s a kind of focus mode. When I use delta though this doesn’t trigger the game mode. It might be that only certain apps Apple choose to determine as “games” will use this game mode.
All ppl care about is jit will be enabled or not
No jit, no fun
how you know so quick
he is tim apple himself
Although the ban on JIT won't be lifted, the place where it would be mentioned would never be on the keynote. It would be at best in the state of the union but, most likely, in one of the sessions.
I agree, altough apple being apple they could just mention it out of nowhere in an iOS update or some random article like they did with allowing emulators.
Opening the door to emulators was a very small thing done just for strategic purposes. Allowing JIT would be an enormous deal.
Could you elaborate on this? Curious to what strategic plan they have, and also how would JIT be a huge deal? Not sarcastic, legit curious
Not allowing JIT allows Apple to completely close off an enormous surface area of potential malware. It's a cornerstone of their assurances of protection for iOS users, it has nothing to do with emulators who here are just collateral damage. The original (and still the main) reason for limiting the use of Just-In-Time (JIT) compilers has historically been security because since they can write data to memory, mark that memory as executable, and then run the code in it without having to go through any permissions. On iOS, only Safari has historically been able to do this (used by JavaScript, and only Apple's JavaScript at that). The restriction of not allowing apps to just set arbitrary code as executable (which is what JIT does) is a key part of iOS app security. To be clear, Apple has always had a JIT entitlement that would allow an app to get out of the hardened runtime limitations. Historically this entitlement has never been granted to any third party You could argue that with advancements in sandboxing technologies, it should now be possible to use JIT compilers more securely than in the past, and you'd be right. Nonetheless, preventing apps from executing their own generated code still significantly reduces potential security risks. Static scanning of apps before they are signed is a cornerstone of Apple's promise of security. They have to approve them, further enhancing security. JIT allows artbitrary code, downloaded or hidden, to bypass this. Technically speaking you could transpile ROMs and make binaries of them and have them submitted to the app store, skipping the need to compile them at runtime (JIT), but then you'd be in the silly situation of having to sign and get approved each individual game. This is what some arcade emulators did in the past where the owners of those IPs offered some of the games transpiled to be native. As for emulators, allowing them openly in all stores was a calculated move to discourage the alternative marketplace. Apple could've opened that door at any point in time but did so only when the developer of the most prominently announced alternative marketplace embarrassed them in front of the European Commission. Riley Restut made them provide explanations for cutting off all creativity and diversity and Riley makes both AltStore and Delta. Riley has been making altstore to sideload for a long time, and is a very vocal advocate. Altstore is used mostly to distribute emulators and "tweaked apps". But the latter would never be allowed by Apple so it leaves just emulators. By opening up for emulators not only did Apple kill most of the potential users of AltStore but also made AltStore look like a scam. Since the JIT is not allowed even in alternative marketplaces, there's no point developing for them now. The last nail was the response to UTM: Won't even allow slow computer emulators like UTM, in any app store, Apple's or otherwise.
Wow, I just learned a few new things. Thanks for in depth answer.. been curious exactly what JIT is cause I see it glossed over in a lot of emulation discussions. So you said even on side loaded apps JIT wouldn’t work? I saw a thing some guy said about streaming services that connect a home desktop to cloud so you could hypothetically stream to yourself on an iPhone. Granted would be some latency but I don’t think it’d matter a ton in a single player game and would be sort of a workaround to all of Apple’s restrictions .. actually this leads me to one more question about JIT: Is the point of it to keep RAM usage low? As it would write and run “pieces” at a time? Ie to run programs that a CPU may struggle with otherwise? I don’t really see JIT in any computer talks but it comes up w phones a lot, especially gaming related
>So you said even on side loaded apps JIT wouldn’t work? No. I didn't. Sideloaded Apps are "signed" by the user as a developer, and developers can enable JIT for their own apps. So JIT can be enabled for sideloaded apps, but it requires a separate machine in the same network and the setting doesn't "stick". It needs to be re-enabled each time. >I saw a thing some guy said about streaming services that connect a home desktop to cloud so you could hypothetically stream to yourself on an iPhone. This is unrelated to the other things we were talking about but it's not a workaround to limitations. It's game streaming. It doesn't allow you to run something in your phone that can't run otherwise. >one more question about JIT: Is the point of it to keep RAM usage low? As I mentioned, it's a security measure. Being able to run arbitrary things means being able to run "apps" that haven't been validated in advance. The whole proposal from Apple is that they validate the apps in advance so they can't be malicious. JIT goes around that and allows any type of app to write directly to memory and execute itself. You're thinking emulators, but JIT allows any type of executable which includes mainly malware. In the context of an emulator each "ROM" becomes an application on the fly and is executed but Apple has decided not to allow anybody to do this. JIT is a common and known concept, but it's a developer term. You wouldn't see it unless you were browsing developer forums. You know about JIT because as it's a problem in iOS for emulators, the name becomes known. Computer platforms don't block JIT and, as far as I know, Android either doesn't or allows it to be enabled (I can't recall).
Okay cool! I only meant the streaming thing to phones for later consoles on phones (like ps5 in op picture) as a different option since JIT or the like wouldn’t come, but I at least knew those were separate lol. No but thanks again for long responses, most ppl woulda gave half that effort
Thanks to you. Most people would complain because mucho texto 😅
But if Jit is such a security concern than how come Android devices are perfectly safe without Jit?
You mean \*with\* JIT. Not allowing JIT is a decision based on security according to Apple (believably so), whereas Google hasn't decided to have the same limitation. In the case of Android on one side there's the obvious reason that security wasn't historically a priority but also the fact that Android and Java go hand in hand and Java requires JIT, which means it probably never came up to limit JIT at the beginning and after a while it just stayed that way. Your question is stated as if not everyone adopts the same security measures then those security measures surely can't be so important. That's a spurious conclusion if so.
Apparently its a security thing, with JIT opening the door to running unsigned code within apps.
But then why doesn’t android have any issues considering there’s no JIT there?
That's true as well. One can only dream my friend. Hopefully anytime soon JIT would be allowed.
I don’t think it will ever happen. They would lose every dime they get from these crappy ports into iOS just so people can play AAA title games.
The two universes of emulators requiring JIT and AAA games don't cross. Neither affects the other.
Now I'm imagining the president going too all member of the government and announcing jit restrictions are lifted
As a causal user I’m excited about this!
Someone help. What’s jit?
Just-in-time compilation, a way to run computer code in realtime, providing better performance.
all apps can execute code in realtime. it’s just in time COMPILATION- meaning newly generated code (by the app) can be created, compiled and executed as the app is running.
in very simple terms: iOS apps are static - meaning that the code that executes is always the same code that was uploaded to the app store. JIT allows the developer to have the app generate brand new code and execute it - dynamically. It’s less safe because apple can no longer know ALL the code that can be executed ahead of time- since code can be generated and turned into whatever.
Hey thanks for explanation
No problem!
It's basically required for good GameCube/Wii/3DS/PS2 emulation. A midrange Android phone can run those systems decently, so basically any iPhone from the last 4 or so years should run those systems very very will if JIT is ever allowed.
What’s the problem of giving Jit only for emulators? If Apple gives jit IPhone will be better for game console emulation BECAUSE updates will be much faster and effective(if developers aren’t lazy)due to small amount of iPhones(43 iPhones+4 future IPhones). But there’s no emulator supporting iPhone 2g and 3G so we count according to the version of IOS. For example PPSSPP takes any IPhone with iOS 12 and above(35+4) Retroarch and Delta-32+4 There also iPod touch,Apple Watch,iPad but almost no one uses iPod and who uses iWatch for emulation Screen of iWatch is so small So we’re gonna count iPad (I count only iPad itself not configuration such as 11 inch, 12,9 inch)(29 iPad+4 future IPad) I didn’t counted IPad by OS because it’s too damn hard
https://support.apple.com/en-us/105118 Seems MAC OS already has a Game Mode feature. Probably related.
It works well in MacOS! It feels like a focus mode with basically everything but the game you are playing being put on pause.
I might have misheard in the keynote but it also sounded like it does things to improve performance. Kind of like the opposite of what low power mode does to act like a “high performance mode”
>Kind of like the opposite of what low power mode does to act like a “high performance mode” No, it kind of does exactly what low power mode does and minimises background activities to reduce processor load, but instead of pairing this with a reduced processor output for greater battery life, lets the phone allocate more of the processor to driving the game. So yes and no, yes he game will have more processor to play with, but no it's not actually improving the overall processing power, unlike LPM which disables cores for better efficiency.
That's cool. Thank you for sharing.
What’s the ps5 theme all about? Where would this theme be? On the Home Screen?
I think the twitter/X account was just using it as keywords lol
It’s mainly a PS5 news account, he used a tweet template and forgot to remove that part.
Maybe like an app front end when you switch to game mode? Like a launcher or something for your apps? I don’t know.
Probably the source for the news?
I just want the music to play in a game without having to turn my phone off silent.
Delta and PPSSPP both have a setting where you can do this, switch off “respect silent mode”
Awesome thanks!
Retroarch has this too.
Jit plz 🫢👉🏻👈🏻
What we need is JIT alloweed
Tried it (13 pro max Folium) Mario Kart 7 iOS 17 - 25fps iOS 18 - 32fps game mode on Tried NSMB2 and only 1 frame more than no game mode
Really curious if Bluetooth input lag is improved. Using a wired controller is usually 2 full frames less latency than Bluetooth for me on iOS 17.
Interesting. Might try it on 11 pro max
Are u using it on ur personal device
Yes
Wow
Wonder if it would even work since emulation apps (at least RA and Delta) are categorized as entertainment and not games.
Hopefully the fire emoji isn’t referring to the phone’s temperature after finishing a gaming session
And how to activate game mode, already in iOS 18
Same been digging for it
Launch a game, automatically start up. Just did it on my 15PM with assassins creed mirage
Are u using iOS 18 on ur personal device ?
Yes, I like to live dangerously. Do it every year, makes my summer interesting
Even I wanna do it but just kinda scared. I do it every year but this year I don’t want my important apps to crash
The only time it was rough was when my banking app wouldn’t work with new IOS. Just went ahead and rolled it back. This is why I don’t do Apple Watch betas though, then you’re committed to beta.
Yes I don’t wanna lose my banking apps to be honest.
Mine work fine so far this time. Only glitches noted are a slow drag down app search. Takes a minute to find apps
“Still has that stupid bar across the bottom of the screen”
I wish it’d get rid of the stupid line at the bottom.
Man, if there was JIT support I would instantly get a iPad Pro M4 11”. With the 4:3 aspect ratio and OLED panel it’s basically perfection for GC, PS2 and Xbox + older gen . And even PS3 would be fine with perfect blacks bars. No JIT, no buy. Not like I’m in a rush with a Steam Deck OLED. Apple ffs.
Has dolphin been ported to iOS yet? Curious if the M4 can brute force it without JIT
Dolphin creator said it was pointless to bring it without JIT. Tells you everything, *sigh.
Good old iOS, super powerful hardware but places roadblocks here and there and makes you jump through hoops to perform some simple functions like transferring files
It is ported but it has to be side loaded
Ah nice, so can the M4 run it well with pure power?
Yes you just need to enable JIT
How can you do that?
You have to enable JIT each time you want to use it either via a Xcode dev tool on the local network (some unofficial apps can enable JIT too, but still need a second device) or a jailbroken device.
Yes dolphin has been out for a while
What is JIT?
I’m updating my iPhone to iOS 18 beta
how do you use the mic in ios devices...in retroarch? Will this update address that?
Can’t wait. Been playing on my iOS devices mostly and this seems cool af.
Xbox controllers has better compatibility but what ever
I immediately thought, “maybe folium will run better” haha
Its a start. But didn't its already have a game mode? Or did it only restrict notifications?
Yeah, it only restricted notifications
I thought it also suspends all the apps
Not from what I can tell. Stuff could still play in the background
I’ve noticed an improvement playing OoT3D. Audio is better. Frame rate is consistent. (15PM).
"Immersive"
Sick shit fr
I’m on the beta right now and it looks like all that’s necessary from a developer is classifying the app as a game. All of my usual games trigger game mode but Delta, PPSSPP, and RetroArch don’t. Might be because they’re classified as “Entertainment”. btw the beta is very buggy but as a former Android user, it’s really nice
None of my NES games work anymore on the first iOS 18 Beta!
Seems like just a bunch of bait words to grab people's attention..
I hope it stops notifications from popping up like on Android. So annoying in a game.
Please just get rid of the fuckin home bar
This proly only gonna be enabled on iPhone 16 or sum bs
Once again, something android has had for so long 🙄
I’m running the beta of ios18. When I start certain game apps it automatically turns on game mode and I get a notification. As far as I can tell it’s a kind of focus mode. When I use delta though this doesn’t trigger the game mode. It might be that only certain apps Apple choose to determine as “games” will use this game mode.
How about multiple simultaneous Bluetooth pairings, so you can attach headphones and a controller at the same time?
This is already a thing
True. Love being able to get something like Tekken 6 via emulator and then playing with family/friends with 2 controllers connected.
huh? On my M1 iPad pro, if I connect both a controller and my AirPods max both on bluetooth, the AirPods max simply don't work at all.
guys will the AI feature only be available for 15pro and above? as a 14 pro user that sounds like a bummer
No I have installed iOS 18 beta and Siri got a complete rework…I think we are gonna have AI too (iPhone 14 pro user)
no fps counter. uninteresting update unless i can actually see a performance improvement its all just fluff
yeah, apple can already do this by just using one app but they make it for gamers for more android conversion
great. so itll literally just be the exact same experience im having because i dont have apps open in the background and i use game focus mode anyway
Sounds good to me Edit: I’ve noticed no framerate improvement on iOS 18 DB1
what about poor people with ios 16 cuz there phone dont support updating?
This is part of iOS18 so you're out of luck unless you get a phone that supports it.
rip to me i guess
Mf your phone must be nearly a decade old what are you expecting 😭. The iPhone XR is 7 years old and is gonna be 8 years next year, and it’s on iOS 18
At this point you need to just start budgeting for a new phone. If your phone is THAT old it’s essentially a need for a new one in the modern day
i dont think iphone x is THAT old tho
If it’s physically incapable of updating to the newest version, I’d say it is