Here are a couple resources for learning iOS:
Intro Books
1. iOS Programming: The Big Nerd Ranch Guide (4th Edition) - This book only covers iOS 7 and Objective-C, but a lot of the same concepts will apply in iOS 8. This would be good intro to iOS and also learning Objective-C. Some of the text might be out of date since the Xcode UI has changed a little bit. I originally started learning with the Beginning iPhone Development book (below), and I read this one after; I thought that the Big Nerd Ranch book went in to more in depth on almost all the topics and I was able to pick a few tips on how to better structure my code.
2. Beginning iPhone Development with Swift: Exploring the iOS SDK - This book is also gives a good intro to iPhone development, but this one is written for iOS 8 and is in Swift if you want to skip the Objective-C part.
Learning Swift
1. I recommend just reading Apple's book on Swift to learn the language. It's available in iBooks here and on the web here.
2. There is also a second part of the book above that covers using Swift with Cocoa and Objective-C, which goes into more advanced topics but is a good follow up read after reading the first part. The iBooks link is here.
A common question I see is should I learn Swift or Objective-C? I think that if you are looking for a job as a iOS developer, you will need to learn both because most likely the company/client already has existing code that is in Objective-C. You can mix and match Swift and Objective-C code, but you need an understanding of both to do so. If you are able to develop an app from scratch, you can probably get away with only learning Swift. It is also good to point out that the 3rd party library support for Swift is very weak right now, so if you don't mind reinventing the wheel (a good way to learn) then this is the way to go. You can also always refer to open source libraries written in Objective-C and convert them to Swift yourself (another benefit for learning both languages).
A common question I see is should I learn Swift or Objective-C? I think that if you are looking for a job as a iOS developer, you will need to learn both because most likely the company/client already has existing code that is in Objective-C. You can mix and match Swift and Objective-C code, but you need an understanding of both to do so. If you are able to develop an app from scratch, you can probably get away with only learning Swift. It is also good to point out that the 3rd party library support for Swift is very weak right now, so if you don't mind reinventing the wheel (a good way to learn) then this is the way to go. You can also always refer to open source libraries written in Objective-C and convert them to Swift yourself (another benefit for learning both languages).
Other resources (tutorial sites and blogs)
1. http://www.raywenderlich.com/ - This site has a lot of useful tutorials for not only beginners but also intermediate and advanced iOS developers. When I was first starting out, I frequented this site and tried to do as many tutorials as I could. Even still today, I find myself visiting this site to continue learning.
2. http://nshipster.com/ - This iOS blog is written by the creator of AFNetworking and has a lot of in depth articles on Cocoa, Objective-C and Swift topics that are commonly overlooked.
3. https://iosdevweekly.com/ - This newsletter is a great way to get a pulse on the iOS community. I've been able to learn about a lot of useful tools and libraries from this weekly email.
4. WWDC videos (all years) - The videos from the WWDC presentations are extremely useful, but can be quite advanced and dry sometimes. If you are unsure of what the best practice of doing something is, I would recommended these videos; It's also a great way to learn about the new things that were introduced in every new version of iOS. Also see ASCIIwwdc.
Hopefully this is a good enough start. There is also always the Apple docs (sometimes confusing and hard to find), Google and Stack Overflow. Good luck!
4. WWDC videos (all years) - The videos from the WWDC presentations are extremely useful, but can be quite advanced and dry sometimes. If you are unsure of what the best practice of doing something is, I would recommended these videos; It's also a great way to learn about the new things that were introduced in every new version of iOS. Also see ASCIIwwdc.
Hopefully this is a good enough start. There is also always the Apple docs (sometimes confusing and hard to find), Google and Stack Overflow. Good luck!
