The Treo 750 shares its chassis with the , resulting in a familiar hand-friendly shape along with the ability to share most accessories ranging from cases through to dongles which connect to Palm's slot-like cable port.
There are, however, several small improvements. The Treo 750 sports softer, almost rubberised side panels plus a similar treatment for the barrel of the stylus for a more comfortable grip.
The 680's gunmetal colour scheme is replaced by a more sombre and more professional matte finish in dark midnight blue, while even the metallic-look fascia has a less reflective "look at me" sheen.
While the five-way navigation button and keypad are also lifted straight from the 680, the four Palm application buttons are replaced by dedicated Send and End phone keys plus a Windows button (for accessing the Start menu) and OK. Above these are "soft buttons" to activate on-screen menus.
We found the Treo 750 exceptionally easy to use one-handed. That said, while keyboards (especially smaller "thumb-boards" like this one) are largely a matter of subjective preference, we felt the same about the Treo 750's keyboard as that of the Treo 680. With their close spacing and relatively deep travel, the stubby keys require precise aim and more than a dash of dexterity to hit even a steady two-finger (or, more precisely two-thumb) speed. Users with smaller and more delicate fingers wil certainly have an advantage here.
The right side of the Treo 750 contains an IR port (relocated from Palm's traditional top-mounted position) and miniSD card slot instead of the Treo 680's larger SD bay. This is the first miniSD card on a Palm device, with Palm telling us it was introduced partly to recover internal space needed by the Treo 750's 3G radio. In addition to the standard miniSD memory card (which isn't bundled with the Treo 750, alas) the slot supports IO cards with functions such as barcode scanning and Wi-Fi. The last one is notable because the Treo 750 has no Wi-Fi, so you'll want to track down a Wi-Fi miniSD card if hooking up to home or office networks or public hotspots is high on your list.
On the rear is a 1.3-megapixel digital camera with self-portrait mirror but no flash -- the camera shoots stills and low-res video clips and is no better nor worse than anything else in its range. But then, you're not going to buy the Treo 750 for its camera. There's also a speaker which fires to the front, with a top-mounted ringer/silent switch carried over from the Treo 680.
The biggest change from the Treo 680, of course, is that when you turn on the Treo 750 you see the splash screen for Microsoft's Window Mobile 5 instead of the Palm OS.
But this isn't Windows Mobile like you've ever seen before. As part of the deal to bring long-time competitor Palm into the Windows fold, Microsoft opened up the Windows Mobile source code for Palm's modification. This makes Palm the only Windows Mobile licensee permitted to modify the core of the OS, so that enhancements can be built into the OS rather than bolted on as additional layers.
(We should note that both Palm and Microsoft have already indicated that an upgrade to the just-launched Windows Mobile 6 is in the pipeline, and demonstrations of a Treo 750 running a beta of Windows Mobile 6 under its pre-release codename of Crossbow have already been held behind closed doors).
Palm's enhancements to the Windows Mobile OS are superb. The main Today screen has been overhauled to include a fast search capability to hone in on contacts in your address book.
The hitlist narrows as you type each successive letter, and you're presented with the option to dial the primary number or tap the centre of the d-nav control to call other numbers, send an SMS or an email based on what contact details are listed for that person.
Any number from your address book (or any new number) can be made accessible as a speed dial button on the Today screen, with similar flexibility in how to contact that person. For added cuteness, Palm allows users to include a photo for each contact on the screen -- although it could be argued that if you call someone frequently enough to earn them a place on the Today screen, you probably remember what they look like.
The Today screen also sports two tie-ins to the Treo 750's launch partner Telstra. At the foot of the screen is a Search field which points to Telstra's Sensis Mobile site for online searching. There's no obvious way to redirect this to, say, Google Mobile, but we're sure a little hacking under the covers will fix that.
More impressive is the set of icons that appear when you dial yourvoicemail box. Styled like the controls on a VCR or CD player they make fast work on playing, deleting, skipping over and saving messages with a tap of the stylus, instead of having to remember numbers on the keypad.
For all that, the interface is littered with some confusing references. The Today screen itself has a Messages field for accessing email and Text Messages for SMS and MMS, while the Start menu lists the Inbox for email (handled via the standard Outlook Mobile client) and Messaging for running the SMS/MMS client.