There is some compatibility between the m!x, Meets, Tamagotchi On, and Some. Compatibility ranges from none at all to some functions to being fully comparable with each other and their respective apps.

Connectivity Chart

Tamagotchi M!x Meets On Some On & Meets App
M!x Play date, Marriage, Transfer Play date, Transfer (from M!x ONLY) None None Only 5 mins (Meets App ONLY)
Meets Play date, Transfer (from M!x ONLY) Play date, Marriage, Transfer, Pet mix Play date, Marriage, Pet mix Play date, Marriage, Pet mix Both Apps
On None Play date, Marriage, Pet mix Play date, Marriage, Transfer, Pet mix Play date, Marriage, Pet mix Both Apps
Some None Play date, Marriage, Pet mix Play date, Marriage, Pet mix Play date, Marriage, Transfer, Pet mix None
On & Meets App Only 5 mins (Meets App ONLY) Both Apps Both Apps None

Credit: https://tamatown.com/tamagotchi-meets-on-%ec%8d%b8/

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