Not sure why this is downvoted. Wikipedia says that Tamagotchi was initally marketed exclusively to teenage girls, whereas Digimon -- made by the same creators -- was deliberately aimed at the male audience.
By the time Digimon arrived, the Tamagotchi hype had already subsided a bit (at least here in Germany). And while I knew more girls with one than boys, there were several boys who did (including myself).
Apparently the Digimon device had a bunch of "social" features - multiple devices could talk to each other (don't remember if it was contact or infrared) - but I think she never met anyone else to test it with.