I figured one way of doing it.
- must have UDID's of all the devices you would like to distribute to.
- go to: Apple Developer Member Center, navigate to provisioning profile.
- add the phones/UDID's to the profile.
- In Ti Studio 3, right click your project > run as > run configurations.
- Under Titanium iOS Devices select your driver as iTunesSync, then select your new provisioning profile. then run your build.
- after it syncs to iTunes, right click on your app and click 'show in finder'.
- copy the .ipa application file and then you can distribute to your users. the app will only work on the devices that you provided UDID's for. The end user must also import the .ipa file to their iTunes to 'sync' to their phone/device.
http://docs.appcelerator.com/titanium/latest/#!/guide/Deploying_to_iOS_devices