The biggest and most obvious feature about the HandEra compared with any other PDA on the market is its high-resolution display. The QVGA screen offers three times the resolution of most regular PDAs - Currently, only some of the Sony CLIÉ models feature the high-res screen. The HandEra 330 has built-in PalmOS extensions to run applications that support high-resolution modes. Basically, if any software you've downloaded supports the option on the CLIÉ, it should also run in high-res on the HandEra. For all the rest of your legacy applications, however, the HandEra can center the window, align it to the upper-left, or scale it to fit.
Scaling seems to work best with any applications that just use text and fields, like a database application. I got rather erratic results with any other program - I tried using some of the Palm Desktop standard games like HardBall - Some ran, but showed obvious graphic defects and pixel dragging due to the software failing to remove the pixels drawn by the scaling operations. Other apps crashed, or weren't scaled properly, pushing the window off the screen. Your best bet is to run your legacy apps in centered mode, and hope that the developer updates it to support high-res screens. With many Palm apps being updated for color support, it's also a reasonable probability that the authors of your favorite app might consider it.
As if the extra resolution wasn't enough for you, the HandEra 330 uses a virtual silk-screening area. This is an incredibly cool innovation - your Graffiti strokes are actually drawn on the silk-screen area as you trace them, which helps anyone get used to the writing system rapidly. Furthermore, the silk-screen is retractable, allowing you to reclaim some extra screen space to read longer e-mails and documents. If the width of the screen annoys you though, having three or four words per line in your message, then you can rotate the screen! The major applications that come with the HandEra support screen rotation, so you can simply change the preferences and your e-mail gets turned sideways. Again, this is another feature that will hopefully get implemented in more apps over time, but I wouldn't count on widespread support for this one, simply because it may be considered to be unimportant compared to other apps.
While we're talking about applications, let's go ahead and mention the ones that come with the HandEra 330. While very few come preinstalled on the unit, the software CD that accompanies the unit contains a few critical applications for your HandEra, namely Quickoffice. Quickoffice is a conduit application that allows you to take pre-existing Word documents and Excel spreadsheets and convert them into a miniaturized format that you can easily manage on the HandEra. Quickword is a reasonably good tool to read over Word documents, and it preserves about as much formatting as WordPad does. Trying to create a new document might be a little cumbersome using Graffiti, but if you have a Palm III-compatible keyboard, you can simply attach that to the HandEra, and type away. Putting in new formatting and other options is cumbersome however, if possible at all - Quickword doesn't support bulleted/numbered lists, varied font sizes, and quite a few other simple formatting options. Quicksheet is quite a bit more robust, on the other hand - It supports cell data formatting, functions and calculations and even charts.