Compiling apps and extensions on device

• This page is a WIP*

Step 0. Aquire an iOS device with iOS 5 or higher and jailbreak it.

Step 1. Installation

Open Cydia (or just use apt-get with SSH).

Install "Tape archive" ("tar" with apt-get) Install "iOS toolchain" ("org.coolstar.iostoolchain" with apt-get) Install "OpenSSH" ("openssh" with apt-get) Install "wget" ("wget" with apt-get)

Step 2. Get the SDK

They are found here: http://iphone.howett.net/sdks/

You can literally use any SDK you want as long as they have the frameworks you need, however it is recommended you use the iOS 7 SDK or higher as the lower ones do not support arm64 (optimized for iPhone 5s and higher).

Right click "Download" on one of the SDKs and copy the link.

SSH into your device and run these commands:

cd /var/mobile
mkdir sdks
cd sdks
wget http://iphone.howett.net/sdks/dl/iPhoneOS8.1.sdk.tbz2 #or whatever SDK you wanted
tar xvf iPhoneOS8.1.sdk.tbz2
rm iPhoneOS8.1.sdk.tbz2
ln -s iPhoneOS8.1.sdk latest

Boom. Your device can fully now compile iOS applications.

Step 3. Creating the app structure

Switch to root (if you already aren't) and run these commands:

cd /Applications
mkdir Test.app
cd Test.app
touch Test
chmod +x Test

Then create a file "Info.plist" in /Applications/Test.app/ with the following contents:

<dict>
    <key>CFBundleExecutable</key>
    <string>Test</string>

    <key>CFBundleIdentifier</key>
    <string>net.iphonedevwiki.test</string>

    <key>CFBundleName</key>
    <string>LOL</string>

</dict>

Then switch back to mobile and run:

uicache

If you did everything right, once the command is done running you should see this on your homescreen:

(On iOS 6 and lower, there would be no lines in the white square)

When you try to open the app, it will crash! That's because you actually haven't written anything yet. So let's make a quick and dirty application really quick. This will not be the best written app in the world but it will have enough explanation for you to understand what you need to do if you want multiple files.

Make 3 files: main.m, TestLabel.h, and TestLabel.m.

main.m:

#import <UIKit/UIKit.h>
#import "TestLabel.h"

@interface LyAppDelegate : UIResponder <UIApplicationDelegate>
@property (nonatomic, strong) UIWindow *window;
@end

int main(int argc, char *argv[])
{
    @autoreleasepool
    {
        return UIApplicationMain(argc, argv, nil, NSStringFromClass(LyAppDelegate.class));
    }
    return 0;
}

@implementation LyAppDelegate
@synthesize window=_window;

-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    self.window = [UIWindow.alloc initWithFrame:UIScreen.mainScreen.bounds];
    self.window.backgroundColor = UIColor.redColor;

    UILabel *label = [[TestLabel alloc] initWithBackgroundColor:self.window.backgroundColor];
    [self.window addSubview:label];
    [label release];

    [self.window makeKeyAndVisible];

    return true;
}

@end

TestLabel.h:

#import <UIKit/UIKit.h>

@interface TestLabel : UILabel
-(instancetype)initWithBackgroundColor:(UIColor *)backgroundColor;
@end

TestLabel.m:

#import "TestLabel.h"

@implementation TestLabel
-(instancetype)initWithBackgroundColor:(UIColor *)backgroundColor
{
    if(self == [self init])
    {
        self.backgroundColor = backgroundColor;
        self.textColor = UIColor.whiteColor;
        self.text = @"rofl";
        self.frame = CGRectMake(20,20,300,300);
    }
    return self;
}
@end

Then run these commands:

clang -isysroot ~mobile/sdks/latest \
      -c main.m
clang -isysroot ~mobile/sdks/latest \
      -c TestLabel.m
clang -isysroot ~mobile/sdks/latest \
       -framework Foundation -framework UIKit \
       main.o TestLabel.o \
       -o Test

If you didn't get any errors, go ahead and open the app again and you should see this:

Error creating thumbnail: File missing