Creating your iOS Development Certificate (p12)

You must have an iOS Development Certificate to develop apps and test them on an iPad. To create this Certificate:

Create a Development Certificate Signing Request

Open a browser and go to Apple Developer website, https://developer.apple.com/membercenter/ and log in.

1. Click Certificates, Identifiers & Profiles.
   
2. Click the Development option.
   
3. Click the Add icon.
   
4. Select the option for iOS App Development and click Continue.
   
5. Leave this browser window open. 
   
6. On your Mac, open the Keychain Access application, which can be found in Applications/Utilities.
7. Click the My Certificates option.
   
8. Click the Request a Certificate From a Certificate Authority... option from the following menu location: Keychain Access > Certificate Assistant > Request a Certificate From a Certificate Authority.
   
9. Enter a valid email address for the User Email Address field.
10. Enter your company name for the Common Name field. (This certificate can be reused for multiple apps that you might create, so you don’t need to enter the app name here).
11. Leave the CA email Address field empty.
     
12. Select Saved to Disk and click the continue button, 
13. Specify the name of the certificate signing request and where to save the file on your machine. Then click Save.
    
14. Click Done on the final screen.

Generate a Development Certificate

Now that you’ve created the certificate signing request file, you need to submit it to the iOS Provisioning Portal to create the required development certificate.

1. Back in your web browser, in the Apple developer site, click Continue to advance to the “Generate your certificate” screen. 
2. Click Choose File, and double-click the certificate request file you saved a few moments ago.
   
3. Click the Generate button.
   
4. Once your development certificate is generated, click Download.
   

Create a p12 Certificate

1. Open the development certificate file you just created (ios_development.cer) by double-clicking it. (This will open the Keychain Access application and the certificate will install itself).
2. Click on the Keys category on the left and then click the right-pointing arrow to open the private key. You should see the certificate beneath the private key. If double-clicking the .cer file does not install the certificate, launch Keychain Access and choose File > Import Items and select the .cer file.
   
3. With Keys selected on the left, right-click the private key associated with your certificate, and choose the Export option.
   Important: right click the private key (highlighted below), not the certificate.
   
4. Specify a name for the file and select the Personal Information Exchange (.p12) option and save the certificate to your machine.
   Please note: It's best to use the word 'development' for the name of your p12 file and you should not use any characters other than a-z, 0-9, hyphens, underscores, and spaces in the filename.
   
5. Enter a password when prompted and click the OK button. (You do not have to enter a password, however, it is recommended).
   
6. Enter the Administrator password for your computer, and click Allow.
   

Now that you have created your development p12 certificate, you can now delete the certificate signing request file (.certSigningRequest) and the .cer file as you no longer need these. You will need your development p12 certificate later so do not delete this.

Creating your iOS Distribution Certificate

You must have an iOS Distribution Certificate to submit an app to the App Store. To create
this Certificate:

1. Go to https://developer.apple.com/membercenter/
2. Log in and click Certificates, Identifiers & Profiles.
   
3. Click the "Production" option under Certificates.
4. Click the "+" button to create a new certificate
5. Select the option "App Store and Ad Hoc" and click Continue.
   
6. Leave this browser window open. 
   
7. On your Mac, open the Keychain Access application, which can be found in Applications/Utilities.
8. Click the My Certificates option.
   
9. Click the Request a Certificate From a Certificate Authority... option from the following menu location: Keychain Access > Certificate Assistant > Request a Certificate From a Certificate Authority.
   
10. Enter a valid email address for the User Email Address field.
11. Enter your company name for the Common Name field. (This certificate can be reused for multiple apps that you might create, so you don’t need to enter the app name here).
12. Leave the CA email Address field empty.
    
13. Select Saved to Disk and click the continue button, 
14. Specify the name of the certificate signing request and where to save the file on your machine. Then click Save.
    
15. Click Done on the final screen.

Now, you will need to generate a production certificate and create a p12 certificate, follow the same procedure you followed for the development certificate.