Update README

README.md

@@ -1,3 +1,61 @@
-# Gifu
+<img src="https://dl.dropboxusercontent.com/u/148921/logo.svg" width="100" />
+Adds animated GIF support to UIKit. For the Japanese prefecture, click [here](https://goo.gl/maps/CCeAc).
 
-Adds animated GIF support to UIImageView.
+#### Why?
+Because Apple's `+animatedImage*` sucks, and the few third party implementations that
+got it right (see [Credits](#credits)) still require you to use a `UIImageView` subclass.
+
+#### How?
+
+Gifu is a `UIImage` subclass and `UIImageView` extension written in Swift.
+It uses `CADisplayLink` to animate the view and only keeps a limited number of
+frames in-memory, which exponentially minimizes memory usage for large GIF files (+300
+frames).
+
+The figure below summarizes how this works in practice. Given an image
+containing 10 frames, Gifu will load the current frame (red), pre-load the next two frames (orange),
+and nullify all the other frames to free up memory (gray):
+
+<img src="https://dl.dropboxusercontent.com/u/148921/figure.gif" width="300" />
+
+
+#### Usage
+
+Use git submodules or drag-and-drop the files in your Xcode project. I can't
+believe I'm saying this in 2014.
+
+Once done, you can call `setAnimatableImage(named:)` or
+`setAnimatableImage(data:)` on your `UIImageView` (or its subclass):
+
+```swift
+let imageView = UIImageView(...)
+
+imageView.setAnimatableImage(named: "computer-kid.gif")
+// or
+imageView.setAnimatableImage(data: NSData(...))
+```
+
+#### To-do
+
+The usual suspects:
+
+- Add documentation.
+- Write some basic tests.
+
+Nice-to-haves:
+
+- Use Reactive Cocoa instead of (sloppy) delegation.
+- Remove side effects from the private functions.
+
+#### Credits
+
+- The animation technique described above was originally spotted on
+[OLImageView](https://github.com/ondalabs/OLImageView), then improved in [YLGIFImage](https://github.com/liyong03/YLGIFImage).
+
+- The font used in the logo is [Azuki](http://www.myfonts.com/fonts/bluevinyl/azuki/)
+
+- Kudos to my colleague [Tony DiPasquale](https://github.com/tonyd256) for helping out with the factory methods.
+
+#### License
+
+See LICENSE.