I have been road testing the iPad for just about two months now and have had the opportunity to use it for work in a number of locales: at the office, at home, in court, in meetings, and on an airplane. As of today, the list of applications available for the iPad has reached 8,675, with around 150 new applications added daily, and, with over two million iPads now in the public's hands, the "is that the iPad?" questions are beginning to wane. People's questions are begging to focus on what the iPad can be used for and, correspondingly, what applications are worth downloading.
For me and others who are using the iPad on a daily basis as part of their workflow, the answer to the "what applications" question is becoming quite clear: The best applications are those that use cloud-based services. Why? Because the utility of the iPad as a compact mobile computing appliance comes from being able to do outside the office what you normally do inside the office. Whether you are working from the office, home, a hotel, or the beach, the services you use need to be universally available regardless of the device you are working from--whether it be the iPhone, iPad, laptop, or desktop computer. Those services that offer applications that make it easy for you to efficiently switch between devices, so that you can get your work done no matter where you are, are the services that will ultimately be the most useful.
In this respect, several iPad/iPhone applications for cloud-based services are emerging as winners.
Dropbox (dropbox.com) - Dropbox is essentially a cloud-based file storage system that allows you to maintain files online. The service automatically syncs your files between multiple devices, including your desktop computers, so that you always have the most current version of a document available. The service is free for up to 2GB of storage, and they charge a small monthly fee for up to 50 or 100 GB. For what I do, 2GB is more than enough space. Dropbox offers free applications for both the iPhone and iPad that give you access to all of your up-to-date files. Also, since it is a cloud-based service, you can share files with others via URL links. One advantage of using the service is that if your hard drive crashes on your laptop, all of your files are backed-up on the system. Also, because it is a web-based service, you can access you documents from anyone's computer, so long as you have access to a web browser.
Good Reader (goodreader.net) - The Good Reader app ($0.99) builds on the availability of cloud-based services and provides an interface for accessing and viewing documents--and of particular interest to me, very large PDF documents. I previously published a detailed review of Good Reader here and I continue to use Good Reader for reading voluminous documents. Not only can you access documents stored in the cloud (such as on Dropbox) but you can quickly and easily import the documents directly from your email server, through iTunes, or over a WiFi connection
Evernote (evernote.com) - I struggled for a while trying to find a good note taking application for the iPad. Ultimately for me, the best solution was Evernote. Evernote is a free cloud-based service (that can be upgraded to a premium pay service if you really need the extra space--which I don't) that allows you to store notes, web-clippings, photos, voice recordings, and many other things in the cloud. You can access your notes from their free iPhone and iPad applications, from their webpage, or from their native desktop applications. I now use Evernote for all of my note-taking needs because you can create, edit, search, tag, and view your notes from anywhere, and they are always kept in sync. If I am in court, I take notes on the iPad Evernote application. I then assign tags to the notes to make it easy to find later. You can also search notes by name, keyword, date, etc. An underused feature is the ability to forward an email to your assigned Evernote email address and the email will be stored on the system.
Toodledo (toodledo.com) - Toodledo is a full-featured cloud-based todo list service. The web-based service is free, and the related iPhone and iPad applications are $2.99--well worth the minimal cost. Your todo list is always kept in sync between the iPhone, iPad, and web service. There are also third party applications that sync with Toodledo, such as Todo for the iPad, which I prefer because it provides a more aesthetically pleasing interface, but it is essentially the same thing, as it uses the Toodledo service to maintain the todo list.