I personally can't go for devices, electronic or otherwise. It's just not personal enough. Too robotic. I don't go for animals either. You know, that whole goat/brine thing gives me the heebee geebees.
However, I will accept tickling from a masseuse or a pedicurist just about any time. I don't find it at all inappropriate. In fact, any time I go for a massage, it's my hope to get tickled by the masseuse. With a pedicure, it's all but guaranteed.
Most therapeutic masseuses won't tickle on a first visit. You sort of have to get to know them, and let them know you. They don't want to be associated with "happy ending" massages. One lady in her forties had been massaging for years and was delighted when I asked her to tickle me. She told me that ticklish laughter is good for the soul, and releases endorphins.
But again, that personal touch as opposed to a mechanical one is crucial for my own experience.