[MUSIC] This next series of lectures, we're gonna prepare you in order to make an application for a next peer-review assignment. In which we go to Instagram and we get, data from Instagram, and particularly pictures from Instagram, and we bring them back into an app that you have written. So there's a reason why we're doing this, and it's because Instagram, unlike Facebook or Twitter is not deeply integrated to the IOS 9 platform. And as a result, you as a developer have to do more work in order to interact with the Instagram web service. Now while you have to do more work, it's actually kinda typical work that you would do if you were engaging with any web servers out there, in order to use the services that they provide. They provide their services through a something called an API. API stands for Application Program and Interface. It was originally designed for that term originally comes from using libraries within a single computer and it's been adopted for applications that use services that are provided by servers out on the Internet, so web services. I guess the screen over here, shows the app that we're gonna try and create in this sprint. What this, your app is gonna do is it show a picture from your Instagram feed and here we have my bright, shiny mug. And that will be replaced with a picture of your choice. You can also see we have a log in and a log out button that reflects the fact that we're gonna be using some network-based security protocols, in order to get access to that Instagram server. And then at the bottom we have a refresh button, so that we can get the most recent photo, if that should change. So we're doing both security on the network and some real time requesting of data. Now we're gonna do this spread a little bit differently, because there are some concepts along the way that we're gonna break out. And we're going to talk about in a more lecture-oriented fashion. So we're gonna intersperse aspects of making this app with lectures about the material. Some of the things that we need to cover are, the login security process known as OAuth 2.0. We're also gonna talk about the UI elements that are use for holding images and we're just gonna give an introduction to that, since this isn't of course specifically about UI. We're gonna look at how to get developer credentials from Instagram. That's gonna require going to Instagram, using an Instagram account and registering as a developer. And then I'm gonna show you how to register a unique scheme. A scheme in the sense of a replacement for http in a URL. We use that unique scheme in order to get responses back from OAuth. We're gonna have a little bit more discussion about dealing with iOS 9 network security. We saw this briefly in the first course in this specialization. We're gonna look at it in a little bit more detail this time around. We're gonna talk about the data transport format known as JSON, because that's how Instagram returns data, and in fact, most web services out there use either JSON or XML. And JSON is the more common example. So we're gonna look at what JSON is. And then finally we're gonna get the data that comes back from Instagram in JSON format, parse it, and then put it into our app like this. All right, so that's the next few lectures, that's where we're going. Let's start by creating the application that we're gonna be building. It's gonna start pretty much like the other ones, where we initialize a single view application. This one's gonna be [INAUDIBLE] aware, then we're gonna build the UI elements. So, yeah, let's do that. [MUSIC]