A couple of years ago, I bought a Splash O2 external battery case for my iPhone 3GS. It made the phone much bulkier, but made the battery last much, much longer. On busy travel, hockey game, or conference days, it sometimes made the difference between having a working phone at the end of the day, or not. So, I charged it up and popped it on the phone before such trips, but otherwise left it in a drawer.
Last fall, I upgraded to an iPhone 4S, but there was no obvious choice of external battery case to buy for it at the time. Apple fixed the new iPhone's initial battery-life woes quickly enough that it hadn't become urgent, and there seemed to be enough flaws in the reviews of the available battery cases that I hadn't made the leap. Deep down, what I really wanted was a slim, affordable, external battery case with solar charging built in, but that's a pipe dream.
The urgency faded even further when I won a weekly giveaway on Order Border's Facebook page for a Miccus Chargeblock Mini, a rechargeable external battery that connects to the iPhone's dock connector. (There are similar devices available for various BlackBerry, Motorola, HTC, LG, and Samsung phones, or with generic USB connectors to cover many more devices.)
Here, too, the reviews are varied, and I would probably never have picked this device from the field of available battery-extender products. But, selling for around twenty bucks, this little gizmo, which comes with a mini-USB cable for charging, is at just about the magic price point. (For free, it was even better! Disclaimer: I received this product for free, but as a consumer, not as a tech writer, and neither Order Border nor Miccus has asked me to write about it or knows I'm doing so.)
Is it perfect? Nope. It doesn't hold its charge for more than a few days in a pocket or glove compartment, and it won't fully recharge the iPhone's battery, which that Splash case did. Typically, it only adds about 25% to my phone's battery charge. Make no mistake, though, for a tiny gizmo that you can pull out of your pocket only when you need just a little more charge, it fits the bill.
I'll still keep an eye out for the perfect external battery case, preferably one that won't add too much heft to the phone or cost too much. For now, though, I'm glad I've got this in my pocket, and you can bet I'll charge it up before each trip.