45 minuten - 1 uur
Basically my sister's phone would no longer charge when plugged in despite using different cords and power sources that worked fine with other iPhones. It most likely got moisture inside of the dock part (she denies that it got wet, but it was slightly wet on the rear of the phone when removing it from the case haha). Regardless, the phone wouldn't charge.
Knowing that the phone was out of warrenty, and she's eligible for an upgrade right around the corner decided to buy this and get to work on it hoping it would solve the problem.
Honestly it was pretty easy. I've done two screen repairs so far and I felt this was easier than a screen repair. Just follow the video guide along with the written guide (it's on Youtube if you if you search iFixIt iPhone 4 Dock Connector).
One thing to note, on the written portion I did not do Step 13-19 on the written guide. The video guide has no mention of it so it's safe to say that's outdated/not necessary for this repair.
Other than that it went smoothly. When I put it all together it was detected on my computer and was able to charge again. Although I overlooked putting the home button ribbon cable and cell service pin in place so I had to open it up again. It was a really easy repair, took me about 30-45 minutes. Shouldn't take more than that if its a first repair.
So basically if your dock connector no longer will charge (and yet everything else works fine), this should work for you too. Although, if its under warranty you should be able to get it repaired/replaced by Apple no problem (as long as your phone wasn't completely submerged in water anyways). If it's not covered or Apple stores aren't plentiful in your area just use this and you're good to go.
Also, if its just a little bit of moisture that got into the dock (or even the headphone jack) and cords won't connect, try putting your phone in a bowl of rice overnight. This sounds really stupid, I know, but the rice can sometimes absorb the tiny bit of water preventing it from stuff connecting to it, and it'll work again. Although this will work if it was a very very minor amount of water, if its water damaged too much rice won't help.
Also in hindsight I would've taken photos of the procedure but I didn't know they had review type things on this site. I hope people read this and get a little something to help them with their repair.