We need to create production and development certificates. Production certificates are used for the App Store, while development certificates are used to verify that you are a team member who allows apps signed by you to launch on a device. Remember that Xcode 9 can now handle this for you, but knowing the process is still useful. Let's start by creating a production certificate first:
- Log in to the Apple developer account, and you will see the following screen:
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- Click Certificates, IDs & Profiles, and then under Certificates, select All.
- Click on the + button at the top right of the screen:
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- On the screen that appears, select App Store and Ad Hoc under Production and then click Continue:
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- The following screen then lists the steps required for creating a CSR file (which we have already created). Click Continue: