This article explains how to enable Developer Mode in your iPhone's Settings, using a Mac computer and Xcode, Apple's software development app.
Steps
Part 1 of 2: Download Xcode on Mac
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Step 1. Open your computer's browser
You need to download the integrated development environment Xcode from Apple before you can take advantage of your iPhone's developer options.
Xcode is only available for Mac computers, with Mac OS operating system
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Step 2. Visit Apple's Developer Downloads page
From here you can download the latest beta that Apple makes available for software developers.
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Step 3. Log in with your Apple ID
Enter your email and password to log into the developer portal.
If you've never signed in with your Apple ID on your computer, you need to verify your identity with a specific code. You can view it on your iPhone or any other device that you are connected to with your Apple ID
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Step 4. Click Download next to Xcode
Under the heading Release Software, hit the Download button next to the latest version of Xcode, 8.3.1 or later. The Mac App Store Preview page will open in a new tab.
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Step 5. Click View in Mac App Store
You will see this button just below the Xcode icon on the left side of the browser screen.
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Step 6. Click on Open App Store in the window that appears
This will open the Xcode page in your Mac's App Store.
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Step 7. Click Get
You will see this button just below the Xcode icon in the upper left corner of the App Store window. It will turn into the green button Install App.
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Step 8. Click on the green Install App button
Press it and you will download the latest version of Xcode, which will be installed on your computer.
Part 2 of 2: Enable Developer Mode on iPhone
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Step 1. Open the Xcode app on your Mac
You must accept the program's terms of use and license agreement when you first open it. This will install some software components and complete the Xcode setup
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Step 2. Connect iPhone to your Mac
To do this, use the supplied USB cable.
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Step 3. Open the Settings app on your iPhone
This is the gray gear icon on your phone's Home screen.
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Step 4. Scroll down and hit Developer
This option will automatically appear next to a hammer icon in your iPhone's settings menu once you connect it to the computer running Xcode. If you see that entry in Settings it means that you have activated your phone's developer mode. Now you can start trying app demos, check logs, and use other developer options on your device.