Take Time to Thoroughly Clean Your iPhone
Has it been a while since you cleaned your iPhone? A good cleaning can improve quality of use and help prevent more subtle problems from mounting over time. So, when you have a moment, get a soft cloth, a little bit of warm water, some Q-Tips, and a bent paperclip or similar object.
Take off your case, and give your iPhone a thorough cleaning, paying attention to every part. Clean all the gunk out of any cracks or ports where you find it using a soft cloth, and wipe away any stains or residue. Don’t use soap or canned air for this step. Also be sure not to stick anything metal into your charging port.