Update README and add some screenshots

README.md

@@ -1,23 +1,38 @@
-# Apollo iOS [![GitHub license](https://img.shields.io/badge/license-MIT-lightgrey.svg?maxAge=2592000)](https://raw.githubusercontent.com/apollostack/apollo-ios/master/LICENSE.md) [![Carthage compatible](https://img.shields.io/badge/Carthage-compatible-4BC51D.svg?style=flat)](https://github.com/Carthage/Carthage)  [![CocoaPods](https://img.shields.io/cocoapods/v/Apollo.svg?maxAge=2592000)](https://cocoapods.org/pods/Apollo)
+# Apollo iOS
+
+[![GitHub license](https://img.shields.io/badge/license-MIT-lightgrey.svg?maxAge=2592000)](https://raw.githubusercontent.com/apollostack/apollo-ios/master/LICENSE.md)
+[![Carthage compatible](https://img.shields.io/badge/Carthage-compatible-4BC51D.svg?style=flat)](https://github.com/Carthage/Carthage)  
+[![CocoaPods](https://img.shields.io/cocoapods/v/Apollo.svg?maxAge=2592000)](https://cocoapods.org/pods/Apollo)
+[![Get on Slack](https://img.shields.io/badge/slack-join-orange.svg)](http://www.apollostack.com/#slack)
 
 Apollo iOS is a GraphQL client for iOS, written in Swift.
 
-Although JSON responses are convenient to work with in dynamic languages like JavaScript, dealing with dictionaries and untyped values is a pain in statically typed languages such as Swift.
+It allows you to execute queries and mutations against a GraphQL server, and returns results as query-specific Swift types.
+
+This means you don't have to deal with parsing JSON, or passing around around dictionaries and making clients cast values to the right type manually. Instead, the structs returned allow you to access data and navigate relationships using the appropriate native types directly. This also gives you nice features like code completion:
+
+![Xcode code completion](/screenshots/xcode-code-completion.png)
 
-The main design goal of the current version of Apollo iOS is therefore to return typed results for GraphQL queries. Instead of passing around dictionaries and making clients cast field values to the right type manually, the types returned allow you to access data and navigate relationships using the appropriate native types directly.
+Because the generated types are query-specific, you're only able to access data you actually specify as part of a query. If you don't ask for a field, you won't be able to access the corresponding property. In effect, this means you can now rely on the Swift type checker to make sure errors in data access show up at compile time:
 
-These result types are generated from a GraphQL schema and a set of query documents by [`apollo-codegen`](https://github.com/apollostack/apollo-codegen). It currently only generates code for a subset of GraphQL queries. Most importantly, fragments with polymorphic type conditions and mutations are not yet supported.
+![Xcode data access error](/screenshots/xcode-data-access-error.png)
 
-For more details on the proposed mapping from GraphQL results to Swift types, see the [design docs](DESIGN.md).
+As you can see, you can conveniently work with your UI code and corresponding GraphQL definitions side by side. Our Xcode integration will even validate your query documents and show errors inline:
+
+![Xcode data access error](/screenshots/xcode-query-validation.png)
 
 ## Getting Started
 
-[Apollo iOS Quickstart](https://github.com/apollostack/apollo-ios-quickstart) is a collection of sample Xcode projects that makes it easy to get started with Apollo iOS.
+[Front Page](https://github.com/apollostack/frontpage-ios-app) is the iOS version of the simple "Hello World" app that lives on our [developer site](http://dev.apollodata.com).
+
+[Apollo iOS Quickstart](https://github.com/apollostack/apollo-ios-quickstart) is a collection of sample Xcode projects that make it easy to get started with Apollo iOS.
+
+If you want the same syntax highlighting for your .graphql files showed in the screenshots above, you can install our [Xcode add-ons](https://github.com/apollostack/xcode-apollo).
 
 ## Development
 
 This project is being developed using Xcode 8 and Swift 3.
 
 If you open `Apollo.xcodeproj`, you should be able to run the tests of the Apollo target.
 
-Some of the tests run against [an example GraphQL server](https://github.com/jahewson/graphql-starwars) (see installation instructions there) using the Star Wars data bundled with Facebook's reference implementation, [GraphQL.js](https://github.com/graphql/graphql-js).
+Some of the tests run against [an example GraphQL server](https://github.com/jahewson/graphql-starwars) (see installation instructions there).