@swiftwitcher Thanks very much for your question!
First off, congratulations on coming over to iOS development! This is going to be a long, but very enjoyable journey so roll up your sleeves and enjoy the ride 
My first advice for you is to get a foundation in the Swift language. Why? Let me give you an example:
Suppose you decided instead of doing iOS development, you wanted to write a novel…in Spanish. Great! The first thing you need to do before learning about creative writing, is to have a solid understanding of the Spanish language. The same goes for iOS development. My suggestion is to take your time and learn the Swift language first. Not necessarily an expert, but a good foundation. This way, you’ll begin to understand the code that is being used in our books, tutorials, and videos.
Between you, and me, I can’t really say which approach you should take. Books vs Videos. I would say don’t rush your approach, which would mean I would recommend (just my opinion) to start with Ray Wenderlich’s books on Swift first, and go through it perhaps once or twice to get a strong feel for the language. The benefit of learning Swift first is that as you learn iOS development, you won’t be wasting time struggling with issues that are language related.
I am now going to say something as someone who once was a beginner as well:
My advice would be to perhaps avoid the video subscription at first. As a beginner, seeing all of the videos right in front of you may be overwhelming, and in some cases, confusing. You may start a series here, and then start a series there, and so on. Ultimately, you may find that you haven’t really picked up any solid skills because you’ve only been “dabbling”. For this reason, I would suggest you buy the book first. Why? You can now focus, and concentrate on JUST ONE thing. No distractions. None. You now can simply tell yourself, “I am NOT going to do anything UNLESS, and UNTIL I finish this book cover to cover.” The books I wish to point out, are VERY hands on, so you’ll force yourself to learn by DOING and not JUST READING. I would recommend also that by reading a book, you’re able to sit back and reflect, and mull over the concepts. Perhaps even highlight or underline sections for emphasis. And perhaps, read it a second time, to ensure the material has sunk. When you finish going through one or two books like this, you will FEEL confident. You will FEEL EMPOWERED, and INDEPENDENT. You can now say, “Yes, I have accomplished this.”
Once you’ve done this, I would say it would make more sense to subscribe to the videos because now you have a foundation to understand them. You are now bringing something to the table. This added confidence will now help you tackle challenging problems because you have already gone through one or two books at least once, cover to cover. You were smart enough to finish those books, so now you are smart enough to go through the videos. Moreover, by having the foundation of having going through the books already, you’ll understand the terms the presenter in the videos is using, which means a better learning experience for you
So my advice is to start with our Swift book, and then go with the iOS by Tutorials book, in that order. After that, then I would suggest you should subscribe to the our videos.
Just my two cents. I apologize if I was out of line in any way. You know yourself best so by all means if you feel differently, follow your heart. You may be pleasantly surprised!
I hope this helps!
All the best!
A million times this!