Characters: Main character Arukotchi, Her arch rival Ohi, and 15 gotchiboys.
Special Features: Pedometer. As steps accumulate, Arukotch rewards you with lots of fun activities.
Comments: This one is slightly larger than tamagotchis and has a ton of different characters. Object of game is for Arukotchi to get proposals from gotchi boys that she meets. Aruk finds lots of little surprises along the way. Some make her more attractive and some make her unattractive or slow her down. Game saves screen shots of each proposal. Goal is to collect all fifteen screens. Unlike tamagotchi, you don't feed or clean up after her. The good thing about Arukotchi vs Digivice is that the activities don't require you to drop everything and see what it needs. When it beeps, the activity will wait patiently for you to turn it on. Came in three colors...pink, blue, white
 

Instructions (15 pages)

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Characters: the chart shows 19 aliens (7 reg + 12 secret ones), but I heard somewhere there were 26.
Game: 2 games - slot game & rock, paper, scissor
Special Features: Reacts with cell phones, radio & micro waves.  Waves make characters change.
Comments: I just started mine for the first time. One thing I love about this one is that ALL the menus and text in the game are in ENGLISH! I'll add more on this one as I get familiar with it.
 

Instructions

Growth Chart

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A combination alarm clock and Tamagotchi (with P1 characters). Approximately the same size as a Yasashii and came in three colors...white/blue clockface, clear red and blue w/yellow trim.

New! 
Instructions and more photos

Bandai also made a similar item for Hello Kitty.  I'm including it here simply because it's from Bandai and so similar to Mezamatchi.

Don't have much info on this one, except that it's a combination calculator and tamagotchi game in one. 

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