64-bit mode is much faster at switching between system code and user code.
I submit that if you are coding and whatever you are coding requires that you be in 64 bit mode, that you should not be using a data card. Vis a vis, a desktop computer designed for such a function OR code such that you can do so in the native mode without forcing 64 bit. There's really no reason in this day and age of solid state drives, 1066MHz RAM, and Core-i processors to be doing code that is so limited.
If using a laptop, can't you hook the MiFi to the laptop to charge from your laptop's battery while its running your MiFi network? I know this would then shorten your laptop's battery supply, but if you have a MacBook at least you would get better than 3 hours (maybe 5 or 6)? I have not bought one of these yet -- but that was my laptop plan -- of course iPad would be limited to whatever the MiFi could give you in battery life.
Two problems. If you're going to plug it into one of the USB ports due to battery concerns you might as well get a data card - which is what I did. Defeats the purpose of a disconnected WiFi device if its battery is so crappy that I'm forced to plug it in. I don't want to plug to a wall adapter or to my computer. I want it to last at least 8 hours without needing a charge. That's really not that much to ask; just make the device twice as thick or increase its surface area to allow for more battery.
Second problem, some of the MiFis will go into tethered mode and not allow you to connect WiFi, in which case if you're forced to share out from the Mac, a clunky solution at best for a device that is touted to not require a computer in order to function. And it doesn't...but the battery life is abysmal.
I'm not asking a lot, just make it somewhat larger so it can hold more battery charge.