I don't really have a great need for a new battery; maybe if it only lasts an hour between charges eventually. I know there are better batteries out there; but...
As for the why; I'm not sure myself. How long can a typical Smartphone last, anyway?
a typical smartphone: dualcore 1.2ghz CPU, dual or quad core 1ghz GPU, 720p display, always-on cellular+4g+bluetooth+gps connections (yes, you use different radios to make calls&texts, 3g, and 4g) powered by a 1800MaH battery
8 hours of battery.
im not gonna say what the new phones coming out are, fairly irrelavant considering the release date of the 3DS (but seriously. GS3, wow.)
You need to compare that to stuff that's not a smartphone, seriously.
ARM chips are ARM chips, in a smartphone, or elsewhere. and as far as form factor, ect go, smartphones are the closest comparison.
The GPU might be able to be better; however: We still don't know the exact chip. Last I checked, the Pica was a series of chips, ranging from different types, with this one being a lot more recent.
Its a Pica200 (pica is the brand, 200 is the model), a single core at 200mhZ. pitiful. yes, there was MUCH better available at the time - say one of the Mali mobile GPUs.
Also, consider that a huge drain is from the backlight.
if they had used an AMOLED screen that wouldn't have been an issue.
You can get more than five hours, if you disable the always-on Wifi, the 3D, the backlight, and keep the sound off; I haven't tried it though.
the 3ds has a 1300MaH battery. what the heck. my old smartphone had a 1500MaH battery and the battery was the size of a flattened AA battery. modern smartphones last 8 hours with the specs i listed above. specs that were avalible for not-very-expensive when the 3ds came out. that's WITH cellular, 4g, bluetooth and GPS always on. and considering the physical size of the 3ds, and how weirdly big the battery is (biggest 1300 MaH battery i've ever seen) they could have DEFINITELY put a bigger battery in.
They focused on making the second screen touch screen work. That ate in to R&D time and money.
you did not just say that.

But the main point here, is that they did manage to put a focus on graphics for this, and even added in an optional features to make others feel impressed.
200 MhZ singlecore GPU, with sub-320p screens = no focus on graphics at all.
. You also have wi-fi on all the time, looking for connections even when there's no-one around. And usually you have the volume up to play.)
i would like to point out the kyocera echo, with much better specs, dual screens, and the same 1300 MaH battery that lasts for 4 hours in dual screen mode (the 3ds is rated for 3-5 hours)
and the LG optimus 3d, with just under 7 hours battery life, and again, much better specs, including a 1500 Mah battery.
63087
I can testify to this, the same thing happens to laptops. I was once watching a movie on my laptop at about 30% battery power. I accidentally hit the shortcut key that turned the wifi on, and in less than a minute the laptop shut off due to low power.

30% = 1 minute? o_O
well, considering that windows laptops shut off at 5%, that's 25% in 1 minute, which means that you have a 4 minute battery with wifi on?? o_O
seriously, what teh eff?
i have an absolutely pitiful battery and i get 45 minutes for my laptop, with wifi on.