Pocket Piano Song Universe

It's half game, half teaching tool, and all fun. We're nuts about Pocket Piano Song Universe ($2.99, available here), which makes it easy to tap out favorites songs and melodies on a tiny on-screen keyboard.

Pick the song you want and the notes descend to the correct keys, showing you just where to tap. The spacing between the notes shows you how long to hold each one and gives you a sense of tempo. You can tell the app to play the song for you, or tap the Learn button and play it yourself.

The app comes with a sampling of songs you can play, or you can search its online directory and find many more that other users have uploaded. Players have the ability to rate songs, so you can scan the ratings first to make sure you're not downloading a dud. If you're feeling musical, you can even make your own player files, then upload them for others to enjoy.

While the app doesn't teach fingering or any other piano skills, it could certainly teach you the notes to play for favorite songs so you can tap them out when you're near a real piano. It's a tiny piano teacher in your pocket.

Slacker Radio

Finally, some serious competition for Pandora. If you've had trouble getting hold of a Slacker G2 player (and boy, do we know how hard it is to get your hands on one), then you'll be thrilled to find you can get the same content on your iPhone for free.

Slacker Radio (available here) is a personalized radio service that goes far beyond the basics. First off, it delivers over 100 stations that actually feel like they were programmed by people, not computers. You'll find music in whatever category you enjoy. But there's more: you can skip up to six songs in each category each day, so you're never forced to listen to something you don't like. You can flag songs you like with a heart, to hear more like that, or ban that song or artist completely.

We like that it feels more like real radio than Pandora. Pandora insists on playing songs in three or four song sets, which cuts down on the variety we want from it. We also prefer Slacker's method of flagging favorite songs. It lets you nudge stations more to your ideal; whereas if you flag a song in Pandora is uses that song as a new starting point for a set, which gives it too much weight.

The biggest downside to Slacker is that it has audio ads in the free version. Pandora only has on-screen text ads, which are easy to ignore. Audio ads are a little too intrusive. An ad-free premium account is available through the Web site (www.slacker.com) for $3.99 per month.

Blood Pressure Helper

If high blood pressure is effecting your health, get BP Buddy ($4.99, available here) and keep track of it. The app contains a log that you can update several times a day. You can even add notes about what stressors were upsetting you. A graph lets you view up to 60 days worth of entries. Ten percent of the proceeds go to the American Heart Association.

Tag Reader

The Microsoft Tag mobile tagging system instantly connects you to more information and entertainment without typing long URLs or texting shortcodes. Simply snap the tag with your mobile phone and Microsoft Tag takes you there. Download the app here.

Light

Use this clever photo app to add interesting light effects to a shot. Select the pattern of light and shadow that you'd like to add, then control the brightness, blurring, and other settings. The effects in Light ($1.99, available here) are grouped into the following categories: breakups, foliage, lights, sky, and windows.

43 Things

What do you want to do with your life? The Web site 43Things.com has been asking people that for years. Members can make a list of the top 43 things that they want to accomplish, then see how many other members have the same goals. Now, members can access their life lists on their iPhones with the 43 Things app (available here). Use it to view goals and mark them as complete.

Incognito

Apple is finally allowing Web browsers in the App Store, and Incognito ($1.99, available here) is a must-have for sneaky surfers. This anonymous browser ensures that your online time remains your private business. Once you close the browser, it erases your entire session. You won't have to worry about clearing Safari's history by hand; use Incognito and it's done for you.

Dice Bag

Here's an app that really brings us back-back to a friend's basement on a sunny Saturday afternoon, when other kids were out playing football. The uber-geeky Dice Bag (available here) lets you simulate rolling all the basic Dungeons & Dragons dice, as well as the most common multi-dice rolls. Good luck and may all your character stat rolls be high.

Shivering Kittens

Cat lovers unite! There are some cold kittens in this game and it's your job to save them. Shivering Kittens ($2.99, available here) asks you to free sweet, little, blue-eyed kittens from their arctic confinement by arranging falling blocks.

The blocks contain two kinds of cats: shivering and frozen. The shivering ones can be freed by grouping them in combinations of five or more. The frozen need to be freed from their ice blocks first, which you do by creating a line of blocks from the left side of the screen to the right. There are 10 levels of difficulty, but the game is pretty challenging right from the start.

The requirements to free kittens are so steep that we could rarely play for long. Still, sweet graphics and simple gameplay kept us entertained.

Shoutcast Radio

Shoutcast Radio (available here) is one of the leading online directories of professionally and community programmed radio stations, and now you can get easy access to all of it through your iPhone. There are over 25,000 stations from around the world and over 500,000 simultaneous listeners at any given time. The app makes it easy to search the Shoutcast directory and keep a list of favorite stations. Plus, you can give your iPhone a shake to call up a random station.

See the next page for the previous week's selection of hot iPhone apps.