Both ($10) and ($15; a stripped-down iPhone-only version is available for $10) offer a full editing suite for Word, Excel, and PowerPoint documents. The extra $5 for Quickoffice will be well worth it to some people, as that suite offers the extraordinarily convenient option to sync documents with cloud hosting services such as Dropbox automatically. This feature is terrific, since it allows you to keep all of your documents up-to-date without having to plug your phone into your computer. Of course, the choice is yours--Documents To Go has plenty to recommend if the automatic Dropbox sync doesn't appeal to you.

One aside: If you're new to cloud storage, you could do worse than signing up with . It's one of the most popular cloud storage services--almost a household name by now--and it gives you a nice 2GB of storage space for free. By default the desktop installer will create a Dropbox folder within your Documents folder, and unless you have reason to be concerned about cloud security issues, I recommend keeping the majority of your documents in there. Not only will the Dropbox folder provide seamless access to your files on your phone, but it will also help to keep them safe in case you ever experience a hard-drive failure.

Getting started with Quickoffice is as simple as tapping the Accounts icon in the bottom-right corner of the start page, and entering the credentials for the cloud service of your choice. You'll need to log in only once. After you've done so, the interface for opening documents is simple: Either choose an application (Quickword, Quicksheet, or Quickpoint) and a document (from your Dropbox folder or from your phone's storage), or skip the first step and use Browse or Search from the start page. The Documents To Go interface, lacking Dropbox support, is even simpler--choose the type of document, and then browse your device or select an item from a list of recent docs.

The document editing interface in both Quickoffice Pro and Documents To Go is fairly clear and consistent on Android and iPhone. Both suites allow you to highlight, cut, or navigate the text by tapping and dragging anywhere in the main body, and both have a menu of formatting and saving options accessible from the bottom of the screen (or the Menu key on Android). The Quickoffice menu scrolls to reveal a familiar Undo arrow, an invaluable tool.