A.1) Flash Builder 4.5(preferably with Flex SDK 4.5.1)
A.2) Air 2.6+
A.3) A registered Apple Developer's Account
You will then need:
B.1) A certificate from your Developer's Account (in iOS Provisioning Portal > Certificates)
* if your certificate has expired, you will then need to revoke your certificate, and renew all provisioning profiles*
B.2) A provisioning profile (in iOS Provisioning Portal > Provisioning)
Steps to build and deploy Flex Apps to iOS Devices
1) New Flex Mobile Project (check those that are needed, check iOS of course).
a) to run in simulator, you just have to select 'On Desktop'
b) to run in device, you will need to select 'On Device' (and then select the appropriate packaging method)
If you intend to run in the device, you will need to configure the package settings.
Where it says "Certificate", input what you derive from B.1. Where it says Provisioning File, input what you derive from B.2.
3) Click Apply and click Run.
4) You will the be prompted to enter the password that has been paired up with your certificate.
5) After that, it will start packaging and it can take several or a very, very long time (if you select the Standard Packaging Method).
6) It will then tell you that it has packaged to an output directory.
7) Right click on the .ipa file and open in iTunes
8) Note that if you have a copy of the app in your iOS device, make sure you have it uninstalled
9) in the App tab of your device in iTunes, make sure your app is checked and then sync the device
10) Run your app in your iOS Device and DONE!