It's not often you come across a new app that deserves consideration for a spot on your iPhone's home screen, but the new Yahoo Weather for most likely will have people giving your current weather apps the boot. I use a mix of the stock iPhone weather app and The Weather Channel app, but will now turn to the Yahoo Weather app first.
The most interesting feature of the Yahoo Weather app is its integration with Yahoo-owned Flickr. It features Flickr photos to match not only the location you are looking at, but also the time of day and current condition. At the top of the screen, you see place and time information, while at the bottom you'll see current conditions and the high and low temp for the day. If you rotate your phone to landscape mode, you'll see a better view of the Flickr photo with fewer graphics.
Tap on the screen and you see a swipeable 12-hour hour-by-hour forecast along with a three-day forecast. Swipe up and you'll see the forecast for an additional fourth day (in addition to the forecast for the current day), plus five more sections: Details, Map, Precipitation, Wind & Pressure, and Sun & Moon.
The Details section provides the real-feel temperature, humidity, and visibility information along with details about the current day and night.
You can tap on the Map to view satellite imagery in full screen. There are four layers to choose from when viewing the map: satellite, temperature, wind speed, and radar. You can't see the radar information in motion, but you can swipe to zoom in and out of the map.
In the upper corners of the app are two useful buttons. In the upper-right corner, tap the "+" to add a new location. In the upper-left corner, the button reveals a menu where you can reorder or delete your favorite locations. Swiping sideways on the screen lets you cycle through your locations.
If a location doesn't have any Flickr photos associated with it, you'll see a generic image. You can, however, add your own Flickr photos to the Project Weather group to be considered for use in the Yahoo Weather app.