When you first launch the app, you'll need to sign up via Facebook or sign in to your account via Yahoo, Facebook, or Google. After logging in, you'll see a layout akin to Instagram's. Running along the bottom edge are five buttons to navigate the main areas of the app. From left to right they take you to the contacts and groups page; the explore page, where you can view interesting or nearby photos; camera mode to snap a photo or grab one from your camera roll; your profile page, where you can view your photo stream and activity; and a section dubbed More that includes search, settings, and a friend finder.
On the Contacts/Groups page, you can swipe vertically through either set of users to view photos as you can with your Instagram feed, but you can also swipe horizontally on a photo to see additional shots from that contact or group. Tapping on a photo expands it, and if you rotate your iPhone into landscape mode, you'll get a stripped-down view with a black background and a play button to start a slideshow. Three buttons sit below each photo to mark it as a favorite, comment on it, or share it via Facebook, Twitter, Tumblr, or e-mail.
The Explore page lets you browse photos that Flickr deems interesting, or you can view photos nearby. Interesting or nearby photos are laid out a bit differently than they are on the contacts/groups page. Here, they are placed two to a row and vary in size, lending the app a vaguely Pinterest feel.
Camera mode provides basic tools but more than you get from Instagram. At the top, you can adjust the flash settings, flip between the front- and rear-facing cameras, and show gridlines. A slider along the right edge lets you zoom. After you snap a shot, you can choose from 15 filters. The filters are similar to Instagram's offerings at first blush, although 5 of the 15 are monochromatic.
Before you select a filter, you can edit your photo. Tap the button with the pencil icon in the upper-right corner of your photo to access 12 different photo-editing tools, from a one-touch enhance button to redeye and blemish removal. There are also two buttons for drawing or adding text to your photo.
Once you have your photo set, you can add a title and description. You can also add location information, which Flickr calls Add a Venue. The advanced options let you add the photo to a set or group, tag a person, or add other tags related to the picture. Lastly, there are buttons to share the photo on Facebook, Twitter, or Tumblr when you upload it.
On your profile page, you can view the photos in your Photostream or see your recent activity. There is a row of buttons that let you view your sets, groups, favorites, photos of yourself, and contacts. If you tap on one of your photos to expand it, you can then tap the "i" button in the upper-right corner to view its information, which includes date and camera information. When viewing thumbnails of your Photostream, you can use the button in the upper-right corner to toggle between larger thumbnails and smaller thumbnails with stats.
The far-right button takes you to Flickr's More section, where you can search for photos, people, and groups. You can also view your upload queue and find friends. In settings, you can set up your sharing options, adjust notifications, and choose an upload size (original, large, and medium) and choose to upload on Wi-Fi only.