Signals is an application for the iPhone that allows users to submit their phone signal strength to a database for the world to view. The idea is that if many people participate and submit their signal strength from various locations, users will be able to easily identify dead zones.

The app is simple enough, with two main functions: view the map of wireless signals or submit your own signal strength. The map is easy to use, allowing you to find your current location, pan, zoom and search for all iPhone signals or only iPhone 3GS signals. You can change the settings to view 20, 40, 60, 80 or 100 signal marks at one time. On the map you'll actually see the amount of bars someone had in a specific location.

Features are a bit lacking in the app, as you can't do anything other than view the signal. It seems like something more could be done here. Maybe, if you tap on a signal, you'd get more information, like what time of day that signal was submitted or a range of signals at that location. For example, sometimes my cell signal fluctuates while I'm in the same area. So, I might submit a signal of five bars, but sometimes it's actually three. That would be good information to know.

To submit a signal you simply tap the plus button. From here, you select your carrier, which is AT&T by default, and your signal strength. The app does not actually read the signal you're currently getting from your phone. You have to manually enter it in. After you select the strength, you tap submit and your signal strength will appear on the map. This process gets a little fishy because you can't edit an entry. If you accidentally, or on purpose, enter in a false signal strength, it's there forever. So, I guess you have to trust that the people entering in the information are being honest.

The app functioned well for me, allowing me to submit signals and find dead zones quickly and easily. The buttons are all positioned well and navigation is fast and smooth. I did have a couple of crashes when I tried to submit a signal and move around the map quickly.

Signals is definitely a useful application, but it's only as good as what is put into it. For me, in my area, I only see a few signal marks. I'm sure it would be more useful if many people were using it in my area, but I just don't see it staying on my iPhone. If you think about it, when you see a dead zone in a certain area, what are you going to do? You can travel around it if you really need to, but if you're going to that area, there's nothing you can do about the dead zone, you'll just know ahead of time. The only good thing I see about this app is if you happen to be in a dead zone and you really need to call someone, you can look at the map to see what direction to travel in to get to a strong signal area. But, I don't think that's reason enough to take up a space on my iPhone. Whether or not this app is useful to you will depend upon your area and how many other people are using it. It's free, so you should at least check it out.