[AT&T Samsung Galaxy S II SGH-I777] pfmahoney:
A couple of months ago, one of my co-worker's Palm Pre phone attempted to swim in a pool and drowned (electronically anyway). My co-worker replaced it with a Samsung Galaxy S2 and when he got it he was complaining about how much he loved his Palm touchstone inductive charger. Basically you just stick the phone near a little hockey-puck thing and magnets align it and it starts charging without connecting any wires.

We thought about it and had this great idea to mod his new SGS2 phone and at the time we thought we were the first to think of this. So, I bought an inductive charging kit on Amazon and we both mod'd our phones and I'm very happy with the inductive charging system.

While lots of people have done it for lots of different phones, this thread is about the i777 and I haven't seen any mod instructions out there for the i777 SGS2.

First you need to get a Palm Pre inductive charging kit. Go to Amazon and search for a Palm Pre inductive charging kit. They run less than $10 including shipping (yeah, seriously, I couldn't believe it either). I paid $8.35 for mine. While you are there, get a Palm Pre AC adapter... the kit is finicky about the AC adapter and most of mine didn't work with it. So that's another $3.70 (inc. shipping), so you are now up to $12 or so.

Once you get it, it should look like this:

And inside it looks like this:

Open the kit box, and you will see a touchstone that you stick on your desk that is the charger and then the Palm Pre case back cover with the inductive coil on it. Peel off the inductive coil very very carefully as well as the four silver circular magnets and try to leave everything intact. Set it aside because when you put it on you want the contacts to line up.

Now comes the fun part, taking apart the phone, soldering the wire, and then routing the wire.

To take apart the phone, your best bet is to watch a Youtube video (that's how I did it), but fundamentally, unscrew the 7 small silver screws and then carefully, use your fingernails (best) to work your way around the gap in the edge of the plastic. Or - if like me you don't really have much in the way of fingernails - use a guitar pick or a thin credit card... like a store shopper reward card. Slide it into the gap and work your way around... not too hard. Don't use anything metal or it will scuff the plastic. Just start in a corner and work your way around, be patient and don't try to take them apart until you've worked all the way around. And if this description doesn't make sense, then watch a i777 disassembly video on YouTube.

Once you are done, you need to solder a wire to a resistor at the bottom. There's a close up here:

You could try to solder to the VCC pin on the USB connector but it's tiny and I personally thought the resistor was much easier to solder to without risking shorting any pins. I suck at soldering so if I can do it, others can too. Just get a fine tip for your soldering iron, get it hot (but not red hot), put some solder on the wire, and then touch the iron to the wire and then the resistor quickly. Do it quickly to make sure you don't damage the resistor or the PCB. It took me three tries but I got it.

Then route the wire.

You can see the wire route. I routed right... if you are looking at it yourself, you might think the the left side looks better, but it's next to the antenna and I thought the right side was less risky. I routed down, across the speaker (the bare black gap at the bottom is where the speaker is), under the PCB, then crossed up, and then dodged the screw slot in the upper right of the battery compartment by tucking the wire under the plastic there. But you don't have to do it like this... do it any way you want (although I'd steer clear of the antenna), you just want to route from the VCC resistor at the botton up to wherever you want to put the contact.

For the ground connection, any of the screws, or the sim slot metal or anything else works. I used copper tape and just routed with the tape to the screw in above the upper right of the battery compartment. But it doesn't matter. The metal of the SIM card slot works too... whatever you want. Ground is easy.

When you are done, it should look like this (more or less):

I used copper tape ($5 from a hobby store, look in the jewelry section) for the contacts, then lined them up with the contacts from the Palm Pre coil by putting the stock cover with the coil onto the separated plastic from the phone and lining them up by looking at them together.

Yes, this mod is not easy, and it voids warranties, but it is magic every time you stick your phone on a touchstone and it just starts charging. I bought a touchstone for my car, and then one for my nightstand. For <$20, I have a car charger and a home charger and it's super easy to just put the phone near the touchstone and let the built-in magnets hook it up.

Things to be careful of:

Do not short anything. Make sure not to short VCC to ground on the USB connector

Do not flip the power connections. Make sure not to tie VCC on the inductor coil to ground in the phone and visa versa.

Don't damage the resistor when you solder to it. Be fast. But get a good connection too :)

I used a multimeter to check for shorts and to make sure that I got VCC -> VCC, GND -> GND.