Do I need a Developer account to download and use Xcode? I'm not going to use it to sell any apps, just want to learn it. And will it affect my current Apple account?
No. A $99 developer account is only needed to have beta access to iOS, Mac OS X, and other software as well as being able to publish ones work to the iOS and Mac App Store.
You can do all that, but if you want to run an iOS app on an actual iOS device, you'll need to pay the $99. It will not charge your Apple ID account unless you specifically request it to do so.
It is done through Apple's site. You can still simulate iOS apps as long as you have the complete source code for the app you want to simulate. As for non-App Store things, you can make nearly anything from a command line binary, to a Dashboard widget, to a 3D first person shooter game in Xcode and compile it to be a native application that you or any other person can run without restrictions.
I'm not really able to give a good answer to that. I haven't used Swift yet or giving it much of a look.
I am a developer and do use it with that account. But I haven't tried Swift yet as I haven't gotten around to installing Mac OS X 10.10.
You're welcome. Enjoy using Xcode.
So just to make this clear for me, I can download the app, code away, and say I were to make a Mac app could I run it without a dev account?
And will it mess with my normal Apple ID making it a paid for account or trick me into automatically paying $99?
Just making sure.
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Do you (or anybody) use Xcode without an account?
I have Xcode (or did at one point) and I don't have a developer account. It's free to download and use.