slippery ceramic tile

My mother just took a bad fall in her own house. The tile is cheap, slippery ceramic tile that chips easily, exposing the terracotta color underneath the white top.

I have seen products that claim to increase grip, either by adding a grippy layer on top of the tile or types of acids that claim to add friction to the tile by creating pores or something similar.

Are these products for real? If they both work, the acid would seem to be a better deal and less likely to create an ugly discolored look, but of course all the products say they work great and don't change the appearance of the tile and are cheap and easy and blessed by angels and all that.

Has anyone actually tried these?

They would seem to be much less hassle than tearing up the tile or putting down a layer of interlocking wood on top of them or such.

Suggestions? Opinions?

Thanks!