1. Get image data via Flickr API, display image using waterfall style. (UICollectionView for

iOS, RecyclerView for Android.)

2. For landscape images, display one image per row. For portraits, display two images per

row.

3. Click on the image will go to the image detail page.

4. In the image detail page, user can save the image to the phone.

5. Code must readable, extensible, maintainable.

6. Support iOS 7 and up.

7. Support different screen sizes for mobile. Be responsive for web/mobile web.

A simple pinterest like layout using UICollectionView and UICollectionViewFlow Layout For more information goto UICollectionView Flow Layout