Keeping your iPad charged without introducing noise in your headsets can be challenging. Not all chargers work in all aircraft. I recently bought two PowerGen 7.2 Amp (36 Watt) Tri-Port USB chargers. They charge my iPad Pro in both the 12 volt Cherokee and 24 volt Cessna 210. I attached Monoprice cables to the panel with little clips to keep the wires out of the way.
I had purchased a MyGoFlight charger but it produced a lot of noise in the Cherokee and intermittent noise in the C210. It works in my car just fine though.
If you are really paranoid, the best way to keep your iPad safe from frying is to charge it before you go. But if you need to charge it, using an Apple iPad charger with an inverter seems to be the safest way to go. There is circuitry built into the charger that protects your iPad from over-voltage and spikes. Plugging directly into a USB power port doesn’t provide the same level of protection.
You don’t need to read the article, but the takeaway is that “Apple’s diminutive inch-cube iPhone charger reveals a technologically advanced flyback switching power supply that goes beyond the typical charger. It simply takes AC input (anything between 100 and 240 volts) and produce 5 watts of smooth 5 volt power, but the circuit to do this is surprisingly complex and innovative.”
So to prevent frying, plug a AC converter into your power outlet in the plane, then plug the iPhone charger into that. It’s a little bit more complicated than just plugging in the USB converter, but not a lot. 24 Volt inverters are a bit hard to find locally but Sporty’s sells an inverter for $50 that should do the job. And these guys have a a two-outlet inverter for $40. You can pick up 12 Volt inverters at Radio Shack and auto parts stores for about the same price.