My iphone wouldn't charge.  The charger wouldn't make good contact when it was inserted into the phone.  I had to ram it in and ram it in and eventually, I could get it to charge, but it was getting worse and worse.   I was thinking I would have to pay to get someone to fix it. 

 

Finally, after several weeks of this, my massive brain kicked into gear and said, duh, maybe there's something in the little hole there that's preventing it from making good contact.  So I got a thin piece of wire and scraped out all kinds of compressed dust.   Now it works great.  

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