What US electronic appliances will work on 220V/240V?

There are essentially two ways to check if your appliance or its charger work on 220V. Usually the fine print on the adapter will give the range, saying something like: "Rated input:AC 100-240V". If the voltage of the country falls in the range specified, you will be fine.

If you can't find the voltage on the charger, try downloading the instruction manual for the charger. Most companies have the manuals online. Somewhere it should also have the input voltage specification.

If there's any piece of equipment that you're in doubt about, plug it on a voltage converter. Step-down converters start around $10; beware that cheaper models won't support much load (one electronic device should be ok for even the most basic models, but not all of them on a power strip). If your converter does both directions, make sure to set the switch correctly, otherwise you could fry your device.

Converters may be cheap, but they're heavy (1–2lb). Most electronic devices are sold worldwide, and manufacturers like to ship the same device everywhere except for the power cord. Even power supplies built into the plug often support both voltages. So there is a good chance that all your devices do work on 220V, but be sure to check first.

If any of these devices charges over USB, make sure you have at least one USB charger. I've never seen a USB charger that cared about input voltage, but that doesn't prove that none exists.

If it's a device meant for travel and it's modern the odds are high that it supports 50-60hz/100-240V power. Always check by examining the power markings on it, though--if there are no markings figure it's 60hz/120V. The only thing I travel with that needs a converter is an electric toothbrush, everything else accepts anything out there.

Note that you generally have to check the powerpack, not the device itself. The only thing on your list I have is a Kindle--look at the plug itself, between the prongs. You'll see it's rated for anything.