Last year, I bought a used iPhone 3Gs that is now well out of warranty. Not a big deal. Only the battery didn’t stay charged all day anymore, and I wondered whether it was time for a new phone, even though mine is otherwise in great shape. Too bad I couldn’t just order a new battery online and snap it in like with previous phones. Except…I could. I just needed a tiny screwdriver, a few other tools, step-by-step instructions, and a lot of patience.

It’s easy to think that smartphones are sealed, enchanted boxes that aren’t ours to meddle with: if something goes wrong, just call up your mobile phone company and get a warranty replacement or buy a new phone. It doesn’t have to be that way.

Apple doesn’t want us poking around in the guts of our devices, and even switched to a different type of screws with the iPhone 4 specifically to keep us out. But that doesn’t mean we have to stay out, or pay third-party repair shops to do the work. If you can tighten the screws on a pair of glasses and follow a manual, you can probably manage basic repairs on your gadgets.

There are a lot of reliable sources for instructions and parts, many of which I’m sure will be named in the comments. For this surgery, I used a battery replacement kit from iFixit, which has user-editable repair guides for devices ranging from mp3 players to cars, and (more importantly) sells the parts you’ll need to make some of these repairs.

iFixit [Official Site]

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