While I can't recommend a single PDA, I'll give you some guidelines and thoughts which should help you makeyour decision.
As far as battery life goes, they're all about the same...a standard battery lasts for approximately 4 hours (more if the backlight is turned off, or you underclock it), but those with user-replacable batteries usually have optional extended batteries, which can give you 8 hours of use without recharging. Since you pretty much need to be able to replace the battery (at least to pop in an 8-hour battery), the Palm line is out...only the Treo 650 (smartphone) has a user-replacable battery. On the otherside, most PocketPC batteries are user-replacable.
For a fast processor and decent RAM/ROM, I'd recommend the Dell X30 (high) or X50v. Both feature top-of-the-line Intel Xscale 624MHz processors, but the X50v has twice the ROM for storage. Plus, the X30 line is in the process of being "retired," meaning it won't be available much longer, and is not able to be upgraded to WindowsMobile 5.0 (shipping soon).
For storage, only the LifeDrive has an internal (4GB) hard drive. However, if you can wait a month or so, the next line of PocketPCs will be announced/available, and will include internal hard drives as well. The reason they are not currently available is that WindowsMobile 2003SE (the current OS) doesn't support them, but WM 5.0 will soon change that. If you can't wait, focus on those that has 128MB ROM, as that will be the minimum requirement once the HD-based PocketPCs come out.
For listening to music, I'd have to recommend a stand-along MP3 player. While the PDA is more than capable of playing music at the same quality, the battery life and available storage is quite limited in comparison. However, if you can wait for a PocketPC with a HD and an extended battery, you'll be in business...that combo will make the MP3 player almost obsolete. (The LifeDrive has the HD, but no replacable battery!)
When speaking of basics, they're native to mid-to-high range PocketPCs, so you can take your pick. The Dell X50v also has a VGA screen...nice, but not necessary since a QVGA screen still looks pretty good. On the Palm end, the screen sizes nd quality vary, but the LifeDrive and Tungsten T5 are both good contenders. Those are also the only two Palms with built-in WiFi...all others require an optional SDIO card.
A built-in camera really knocks out some of the best PDAs, including everything Dell has to offer. Plus some employers don't allow you to bring cameras to work. Thus, I'd recommend getting a seperate digicam, or one that that is SDIO-based (plugs into your SD card slot). However, since most are of low quality, I'd stick with a seperate camera all together.
As I mentioned earlier, I'd take the X50 over the X30 simply because the latter is not considered obsolete. On the other hand, if you can wait, I'd save the money and pick up one of the "X70s" when they come out...internal hard drives are a key feature in all future PDAs.
Finally, I'd like to note that all current PocketPCs (including the X30s and X50s) run the same OS, right down to the version. The difference is that the OS is customized for each series' hardware. thus, glitches will appear in an X30 and not in the X50, and vice versa. However, patches are released to fix most known problems, so any problems experienced should only be for the short-term. Plus, the X50 (though not the X30) is due to receive WM 5.0 shortly, which will enhance its features and reliability...a plus no matter how you look at it.
Hope this helps,
John
P.S. I only spoke of the Dell line, as I've found them to be the more economical choice. HP, Acer, and other companies make just as high quality PDAs, but their prices are usually $100+ higher for the same specs.
Okay guys, I was wondering if you can help me pick the right handheld for me.
One of the main points is that I'm about to be a medic intern. Ya know, loooooooog shifts so good battery life is a must (user-replaceable battery would be ideal, not only for a spare one but also for when it dies).
Also, a fast processor and decent amount of memory and of course lots of space to store digital books and programs in it.
Yes, I do intend to get a SD card and all but I wonder if I'll need a built-in HD, specialy cause as far as I know my options would be limited to the Palm LifeDrive, or am I mistaken?
I'd like lots of space cause I'm a music addict and I was hoping to be able to have a good mp3 player alltogether, but maybe would be wiser to just buy a separated mp3 player - what you guys think about that too?
Apart from those specifics, gotta have the basics: bluetooth and wi-fi, nice screen. I'm used to windows interface, but that's not an issue.
1.2 or + megapixels cam would be handy but also not THAT essential (can always get a really good separated digital cam).
No phone integrated needed.
I was considering the Dell Axim X30 but I'm not so crazy about it's design and I've been told the software it's kinda tricky. I wonder if the x50 series is any better.
Oh as far as cost goes, I'd only like it not to be outdated too fast and I'm up to spend some 500 bucks on it.
Thank you so much!

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