But it's still early days yet. Apple gave only a chosen few developers early access to the iPad -- everybody else had to make do with software simulators and homemade cardboard mockups. They rushed their apps to market, and it shows. Many of the early apps are buggy and missing features.
These are the best apps I've found so far. They are all iPad-optimized, not iPhone apps stretched to fit the iPad. They get the job done, they're fun to use, and several of them are free.
1Password encrypts, stores and organizes your passwords and other private information, and it automates log-ins for Web sites and other Internet services. You can also use it to store credit card numbers, bank account numbers, ATM PINs and more. 1Password is an extremely useful app for both the Mac and the iPhone, and now it's available for the iPad too.
The iPad version is more like a grownup application than its iPhone counterpart, although it's still missing some of the capabilities of the Mac product. In landscape mode, you get an easy-to-navigate three-pane view of your information and you can browse through entries alphabetically or using the search function.
You can store any information you want using 1Password's preconfigured templates and categories. For example, Logins is where (obviously) you store your Web usernames and passwords, Wallet is for credit card numbers, and Identities is where you can store separate e-mail addresses, phone numbers, street addresses, etc. for work, your personal life, your secret spy identity or whatever.
1Password for iPhone includes a very handy bookmarklet that installs in Mobile Safari. If you're browsing a site that requires a log-in, tapping the bookmarklet will automatically shut Safari, switch to 1Password and call up the correct username and password for the site you're browsing. Unfortunately, that bookmarklet doesn't work on the iPad version. Vendor Agile Web Solutions says it's working on adding it to a future version. Until then, 1Password has its own built-in minibrowser that you can use to automatically log in to password-protected sites.
The latest release of 1Password Pro contains both the iPad and iPhone versions. It's priced at $14.99 and is available as a free upgrade for existing users of 1Password Pro on the iPhone. For iPad owners who don't have an iPhone, 1Password is a $6.99 stand-alone program.
Instapaper is simple and highly addictive. If you're browsing the Web and you find a long, meaty article that you don't have time to read right away, you simply click a bookmarklet in your browser, and that article is instantly saved to a queue of articles at Instapaper.com. Later, when you have time to read, you can call up your queue of articles and dig in.
While this is a great iPhone app, it's even better on the iPad with its bigger screen and better graphics resolution. The iPad and iPhone apps not only download articles for offline reading, but also format the articles for on-screen reading by removing clutter, changing the font and automatically scaling the graphics. You can move through articles by either tapping the screen to turn pages or tilting the device forward or backward to make the article scroll. (It's possible to accidentally tilt the iPad and start scrolling when you don't want to, so I prefer to tap the screen to turn pages.)
Instapaper Pro runs on the iPhone, iPad and iPod Touch, and it's priced at $4.99. The latest version, written for the iPad, is a free upgrade for existing users of Instapaper Pro. There's also a free, ad-supported Lite version for the iPhone and iPod Touch, but it lacks several features, including support for tilt-scrolling, tapping the screen to turn pages and sorting articles in folders. In addition, Instapaper Pro can handle 250 articles but the Lite version only handles 10.
It lets you buy and download books from Amazon's Kindle store and read them on any device: a PC, a Mac, an iPad, an iPhone, a BlackBerry or a Kindle reader. As you read, the service saves your place, so if you read a few pages on a Kindle device but later switch to an iPad and then to an iPhone, you can instantly pick up where you left off each time.
Both the iBooks and the Kindle apps are free and have huge selections of free books, courtesy of Project Gutenberg and other Internet sources.
Which one should you use? Whichever one you need to read the book you want to read.
For example, while I think the Kindle app has a slight edge because of its multiplatform support, the iBooks app had the one book I've actually shopped for since I got the iPad, while the Kindle didn't. And they both use Digital Rights Management (DRM) for many titles, which means you don't really own the books -- you're just using them, and you lose access if the software vendor discontinues support.
If you're a Netflix fan, this one is a must -- an app that lets you watch streaming movies and TV shows from your Netflix queues on your iPad.
The user interface looks as though it's just a Web browser pointing at the Netflix Web site. If you stop watching a movie partway through, the app is designed to remember where you are and resume again after you close the app and return later, no matter which service you use to watch the movie. That's a nice feature, but I found that it worked irregularly -- sometimes the app remembered my place, sometimes it didn't.
Fortunately, you can go back or fast-forward by dragging your finger along a horizontal scrollbar at the top of the screen. You can also tap a button at the bottom of the screen to rewind 30 seconds.
In addition, while the video streamed smoothly, without any jerks or stops, I found that the site itself seemed slower than usual, both in the app and in the iPad's Safari browser.
The app itself is free but requires an unlimited rental membership from Netflix, which starts at $8.99 per month.
Apple's Pages is an impressive little app. It's a fully functional slimmed-down word processor that costs only $9.99. It has all the basic capabilities you expect from a word processor: You can write and edit, format text, embed images and charts, and more. For layout, you can move things around with your fingers or resize them by pinching with two fingers.
Pages can import documents in two formats: Pages '09 for Mac and Microsoft Word (Office 97 and later). It can export to Pages '09, Word 97 or later and PDF
As with many iPad apps, you turn the iPad to change modes. In landscape view, you get a full-screen view of your document; in portrait mode, you get a toolbar at the top. (You can make the toolbar disappear by tapping a button -- it took me a couple of minutes to figure out how to bring the toolbar back by tapping on the text.)
The biggest problem with Pages is that it doesn't really sync with the desktop -- it just imports and exports files. And worse, when you import Pages or Microsoft Word files from the desktop, the iPad app strips out important metadata, such as running headers and footers, section breaks, comments and bookmarks. That makes it hard to switch back and forth between your iPad and desktop while editing a document.
There are already several Twitter clients available for the iPad. I've tried a few, and TweetDeck is my favorite.
It's a version of the free desktop client that's popular among Twitter power users. It has the familiar multicolumn view, which you can customize to show messages from all your friends, @mentions, direct messages, saved searches and your Twitter lists. TweetDeck also shortens URLs.
There are some rough edges. In portrait view, the upper third of the screen is just wasted space, filled with the TweetDeck logo and nothing else. That's where you compose your tweets or view individual tweets. I wrote the developers to ask about this; they said they did this on purpose, to keep that upper third as a blank workspace. Hopefully, they'll come to their senses and let the composition and other windows appear as pop-overs, which is how most other apps do it.
Links are not clickable in the tweets column -- you have to open the tweet separately and tap the link. Judging from the comments on the App Store review and on Twitter, many users don't know that trick; they think links don't work at all.
Also, TweetDeck for the iPad is missing one of my favorite features of the desktop app: the word cloud of trending topics on Twitter. It's an at-a-glance way to tell whether anything important is happening in the world and get a general idea of what that news might be. The developers say they're working on a new way to display trending topics that will roll out on all platforms soon.
Things is the control panel for my life. I depend on the Mac and iPhone versions, and I'm happy to see developer Cultured Code was quick out of the gate with a $19.99 iPad version. This version does all the basic tasks that the Mac and iPhone versions do: It keeps to-do lists with start and due dates, and organizes those lists into projects, areas of responsibility, next actions and more.
The iPad version has an attractive interface that looks like a ruled tablet of white paper. When you change projects or areas, the sheets of paper seem to curl upward, like a page that's turning.
You can sync your Things data among the iPad, iMac and iPhone versions as long as they're all on the same network. Simply open all three apps at the same time and stand back -- they'll take turns syncing to make sure all three apps are running copies of the same database, and will even prompt you on the Mac to re-open the iPad or iPhone version if you shut them down prematurely. The progress bar is kind of entertaining to watch, too.
Some features from the desktop are still missing in the iPad version -- most notably the ability to duplicate projects. And syncing among all three apps is somewhat slow. The iPad and iPhone apps tend to lose their connections and have to be restarted once or twice.
Things for the iPad, Mac and iPhone will cost you $80. Many of the reviewers in the App Store say that's too much. I think it's worth it -- I use it all day, every day. But you might feel differently.
The iPhone comes with a weather widget among its pre-installed apps, but that app is missing from the iPad. That means you need to either check the weather on the Web or download an app. My favorite app so far: The Weather Channel's free offering.
The app is a candy store for weather geeks. You can use it not only to check your local forecast, but also to find out the day's sunrise and sunset times without having to dig too deeply.
And you're one tap away from a three-hour forecast, which is handy early in the morning or late in the afternoon when you can expect the weather to change rapidly.
You can also look at interactive weather maps and severe weather advisories and watch video forecasts from The Weather Channel.
The app was slow to start up, and it crashed once or twice the first few times I ran it, but since then it has run smoothly.