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iPhones are ridiculously picky when it comes to finding a mate- um charger. And knowing why doesn't really make it any easier to understand why. If anything it baffles me more.

So, let's start with appliances that are not phones. Think Bluetooth headsets, keyboards, earbuds, whatever. Those are simple devices. They see 5V on the VCC line and 0V on ground, and they will charge at whatever current they are meant to. Usually it will not exceed 200mA, and the USB 2.0 spec allows for up to 500mA from any USB outlet. So that's perfectly reasonable to be done without any fuss whatsoever.

Phones on the other hand are smarter.. some might say too smart for their own good. In this case I will only cover Android phones, because while they are smarter than they perhaps should be, they are still reasonable.

So if you connect an Android phone to the same 5V VCC and 0V ground, while leaving the data lines floating, the phone will charge at 500mA. This is exactly to be within USB 2.0 spec, as mentioned earlier. Without the data lines, the phone has no way to tell whether it *can* pull more, without *actually* trying to pull more (potentially frying a charger that's not rated for it). Now in an Android phone you can tell it to pull more, in a fairly straightforward way. You just short the data lines together, and the phone will recognize this as a simple charger that it can pull 1A from. Note that shorting data lines is not a bad thing, we do it all the time. It is just another term for making a connection between 2 points. Android does this right. Also note that shorted data lines cannot be used to send data. They are inherently pulled to the same voltage level, probably 0V but not sure.

And then the iPhones come in, Thinking Different. The iPhones require you to pull the data lines to some very specific voltage levels. And of course it's terribly documented because iSheep just trying to use their Apple original white nugget charger overseas and shit like that. I do not know which voltage levels they are (please let me know!), but it is certainly not a regular short. Now you connect the iPhone to, say, a laptop or something to charge. An Android phone would just charge while keeping data transmission disabled (because they can be left floating or shorted). This is for security reasons mostly, preventing e.g. a malicious computer from messing with it. An iPhone needs to be unlocked to just charge the damn thing. I'm fairly sure that that's because the data lines need to be pulled up, which could in theory enable a malicious computer to still get some information in or out of it. USB data transmission works at at least 200mV difference between the data lines. It could be more than that. So you need to unlock it.

Apple, how about you just short your goddamn data lines too like everyone else? And while you're at it, get rid of this Lightning connector. I get it, micro USB was too hard for your users. I guess they are blind pigs after all. But USB-C solved all of that and more. The only difference I can think of is that the Lightning connector can be a single board with pads on either side on the connector, while in USB-C that could be at the socket end (socket being less common to be replaced). And at the end of the day, that really doesn't matter with all the other things that will break first.

Think Different. Think Retarded. Such tiny batteries and you can't even fucking charge them properly.