OP here. I see some GFCI single outlet adapters on the market, but no GFI (and I'm not sure of the difference). If it matters (I think it does), some of the places I've been have used outlets that aren't even grounded, which further complicates the whole surge protection defense of sending excess current to ground.
GFI's are required in the US in all newer homes, they are a fast tripping device, the outlet normally located in the bathroom. One outlet can protect an entire line.
Grounding protection is required for personal protection alone. If a country is too cheap to pay for the extra wire, I'd give serious consideration of using one's incoming metal water pipes as the third wire (think of the kids).
Here's a question: I have a cheap international plug adapter that has "surge protection" built-in in the form of a standard user-replaceable fuse. What about using that, and maybe even putting in a lower-rated fuse?
According to others replies your power supply should be well protected, situations like yours taken into account. The fuse a bonus allowing you more control. Amperage is your concern here, phones, computers, what have you; require a specific amp rating to charge, anything lower can take hours longer to charge if at all.