PostPet (ポストペット, Posutopetto) is a hybrid virtual pet and email client software developed by So-net, first released in Japan in November 1997. The software is designed for computer novices. It takes place in a virtual room, allowing the user's pet to send and receive email messages. Multiple versions of the software have been released over the years, and the franchise has received adaptations into other forms of media, such as an anime series and multiple video games.
The software was successful and well-received for its appeal to new computer users, especially children and young women, with over 100 thousand copies sold in less than a year. On the other hand, critics and journalists have noted that it is not well-suited for professional use.
Overview
PostPet takes place in a virtual room, which can be decorated to the user's liking[2] using plug-in software,[3] where the user's pet resides.[4] When a user receives an email message from another user of PostPet, their pets interact with each other on-screen as the message is exchanged. When a reply is sent, your pet temporarily disappears in order to deliver the message.[5] Pets start out inexperienced at deliveries, and may find themselves going on detours. The pets will also write messages to the owners from the delivery destination, updating them on what's happening, and sometimes for no reason at all but to chat.[4] They may even send messages out to other addresses of their own accord,[6] often about their owner,[7] and will keep a personal diary.[2]
Users can feed their pets a variety of treats,[6] though they do not die if they are not fed. At the end of a pet's lifespan, they leave, and the user is able to adopt a new pet.[8] The user can pet or hit their pet using their mouse cursor, which invokes a positive or negative response respectively. Pets become dirty while delivering mail and require baths to be cleaned. Pets' mood depends on their success in delivering mail,[4] and they cannot deliver mail if not properly cares for.[3] PostPet 2001 introduced the ability to give your pet toys, which they have unique reactions to.[8] An online community service with gameplay elements was also offered to users of the software, called PostPet Park,[9] available with a subscription. The service offered downloads for new toys and snacks,[3] among other features.
Development
Development of PostPet began in 1996. It was created by Kazuhiko Hachiya,[4] intended to be an easy-to-use and fun email client for novice computer users.[5] Kazuhiko says that he was inspired by messenger pigeons and traditional mail when developing PostPet,[3] as well as a dream his then-girlfriend had about a teddy bear delivering letters.[10]
It officially released in November 1997,[7] and would later be released in English and Chinese language versions.[11] Support for Windows CE came in June of 1999,[12] with a dedicated CE device, the Pocket PostPet, following in April of 2000.[13] An IBM ViaVoice compatible version would release on September 10, 1999.[14] The software came pre-installed on some computers around this time,[15] including Sony's Vaio line and Apple's iMac.[8] An updated version of the software, PostPet 2001, released in December 1998,[8] and a third iteration, PostPet V3, released on December 4, 2002.[16] Pets from previous versions of PostPet could be transferred to the new versions.[8]
Characters
Original version
Momo (モモ)
A pink teddy bear, portrayed as a small child between the ages of 3 and 10 years old. They use childish speech patterns and struggle to express themselves, often saying "..." instead when they can't find the right words.[4] They are the representative character for the software[17] and are also used as a mascot for So-net.[18] They were also once used on Sony Bank's website as a virtual accountant.[2] Their official profile describes them as laid back, but a little stupid.[19]
Furo (フロ)
A purple mixed-breed cat, portrayed as a young adult between the ages of 15 and 20.[19] They are prone to running away, and can be bossy. They write emails to the user often, but are quick to disappear.[4] They have a tempermental personality and need quite a bit of attention.[3]
Sumiko (スミコ)
A long-lived tortoise, portrayed as an adult between the ages of 20 and 92. They use the most advanced language of any character[4] and tend to write long letters. Their official profile describes them as being patient, but withdrawn.[19] They have also been described as "argumentative but ironic", and a writer of interesting emails.[3]
Mippi (ミッピ)
A yellow rabbit, portrayed as a child between the ages of 4 and 14.[19] They are somewhat lonely and a bit scatter-brained, and always seem to seek attention from the user.[4] They have a keen eye for treasures, often finding them during deliveries.[19]
PostPet 2001
John (ジョン)
A brown dog, portrayed as a young adult between the ages of 14 and 20. They enjoy going for walks.[19] They like to make people laugh, and have a strong sense of duty. They were named after a real life dog owned by Kazuhiko Hachiya's parents.[8]
Ushe (ウシェ)
A penguin-possum hybrid. They are portrayed as an adult between the ages of 18 and 30, and like to read.[19] They have a "cool" personality, and carry mail in a pouch on their stomach. The developers chose their name to sound Singaporean, as a Singaporean version was planned for release.[8]
Jinpatchi (じんぱち)
A hamster with a big mouth, portrayed as an adolescent between the ages of 10 and 14. They deliver mail quickly, but sometimes forget to send messages due to their sleepiness.[19] The male and female versions have different personalities. They run away much less often than the other pets, but spend a lot of time sleeping. They have the shortest lifespan overall. They are named after one of the developers, Michio Kitamura's pet hamster.[8]
Shingo (シンゴ)
A mecha with a mind of its own, able to operate even when unplugged. It is usually shaped like a computer, but can transform. It enjoys listening to music, and is vulnerable to damage from water. It is portrayed as a teenager around 14 years old.[19] It is named after the manga My Name Is Shingo.[8] In PostPet V3, it transforms into Shingo R.[16]
PostPet V3
Komomo (コモモ)
A smaller pink teddy bear, portrayed as a teenager between the ages of 12 and 18. They are described in their official profile as cute, clever, and sharp-tongued, as well as being selfish. They want to become the new face of the brand in place of Momo.[19]
Takechiyo (竹千代)
A younger version of the robot postman character who delivers mail, portrayed as a young teenager between the ages of 12 and 15. They write emails that contain a lot of naive statements and tend to nitpick what the user writes.[19]
Cultural impact
PostPet was highly successful, selling over 100 thousand copies in less than a year.[7] The software is particularly popular with children and young women,[20] though Kazuhiko says that the program's userbase is more evenly split between genders and primarily consists of adults.[3] Various forms of merchandise have been made based on the characters, including stuffed toys[20] and figurines.[8][21] Momo is a popular character in Japan for mobile phone charms.[22]
A spin-off version intended specifically for children, PostPet Kids, was released in 2000, featuring menus in hiragana and more simplified text.[23] In 2001, Taito opened a PostPet-themed prize corner at their Shibuya store, named PostPet Fun Factory.[24] A mobile version launched for J-Phone cellphones in 2003, which could communicate with the PC version.[25][26] A webmail service, Webmail de PostPet,[27] was launched in 2005 and lasted until 2010 – though people would still be able to register for a PostPet email domain for a few years after its closure.[2] In 2010, a Twitter client named PostPetNow, that would allow the user to exchange DMs with their pet, was being developed, but ultimately never released due to API changes.[17]
A crowdfunding campaign on Campfire for a virtual reality project was launched in 2016 to celebrate the 20th anniversary of the software,[20] which would be held as an event in August and September of 2018.[28] A messaging app for smartphones, PostPet Go, was announced to be in development in 2020 with an unset release date.[29][30]
Reception
Reception of PostPet has primarily been positive. Internet Watch says that the software is good for those who are new to using email,[4] and Yuko Hasegawa writes in Leonardo that the software's use of cute pet characters "makes us more resistant to the stress brought on by computer problems".[31] Lisa Baggerman says that PostPet "makes receiving email both fun and friendly for new users".[3]
On the other hand, reporters expressed that the software is of little use in a professional setting. Newsweek's Kay Itoi says that the software is "slow and lacks the versatility of more serious mailers", pointing out its lack of common features such as the ability to have multiple mailboxes or to send email to multiple addresses at once.[15]AERA's staff calls the pets' tendency to forget to send mail cute, but an inconvenience.[2] Baggerman writes that "messages delivered by an adorable, playful pet" are unlikely to please a CEO, but goes on to note that general use wasn't the intended purpose of PostPet.[3]
Awards
Year
Award
Category
Result
Ref.
1997
Multimedia Grand Prix '97
Minister of International Trade and Industry Award
PostPet Momobin (ポストペットモモ便) is a CGI anime series that aired on TBS Television from 2004 to 2005.[36]
Video games
PostPet Gameland (2000)
PostPet Gameland was an internet-based game for Windows and Macintosh computers, released in 2000. A monthly fee was required in order to play. Minigames could be played using medals, which could be earned through in-game jobs.[37]
PostPet Paradise (2008)
PostPet Paradise was a RPG-like sugoroku game for I-mode mobile devices, released on May 26, 2008. A Yahoo! Mobile version would release in July.[38]
PostPet DS (2009)
PostPet DS: Yumemiru Momo to Fushigi no Pen (PostPet DS 夢見るモモと不思議のペン) released for the Nintendo DS handheld on December 24, 2009. The game takes place on "PostPet Island", where the player is the only human resident. It received a positive review from 4Gamer, where it was described as cute and relaxing.[39]
^ abcde"消えた!?ポストペット「モモちゃん」は有名銀行に"転職"していた!!" [Missing!? PostPet "Momo-chan" has "changed jobs" to a famous bank!!]. AERA DIGITAL (in Japanese). 2015-02-26. Retrieved 2025-09-30.
^ abcdefghiBaggerman, Lisa (2000). Design for interaction: user friendly graphics ; print, web, product, environmental. Gloucester, Mass: Rockport Publ. ISBN978-1-56496-652-0.
^ abcdefghi"今注目のメールソフト、ポストペットで遊ぼう！" [Have fun with PostPet, the popular email software!]. Internet Watch. 1997-10-13. Retrieved 2025-09-11.
^ abFox, Robert (1999). "Email Pet". Communications of the ACM. 42 (5): 10. ISSN0001-0782.
^Mann, Charles C. (2001). "Why 14-year-old Japanese Girls Rule the World". Yahoo Internet Life: 102. PostPets are the brainchildren of Kazuhiko Hachiya, an antic engineer-artist who in 1995 dreamed about a teddy bear carrying letters from his then-girlfriend. Inspired by his dream, he made the first PostPet to amuse her.
^"So-net、カシオ、ドコモら、ポストペット専用端末を開発。4月12日より発売" [So-net, Casio, Docomo and others develop PostPet dedicated terminals, to be released on April 12th]. Internet Watch. 2000-04-04. Retrieved 2025-09-11.
^"ソニー、ViaVoiceに対応し、音声で操作できるPostPet" [Sony's PostPet is compatible with ViaVoice and can be operated by voice]. PC Watch. 1999-06-27. Retrieved 2025-09-11.
^ abKuwamoto, Misuzu (2002-09-18). "SCN、愛玩電子メールソフトの最新版『PostPet V3』を発売" [SCN releases the latest version of its pet email software, PostPet V3]. ASCII.jp (in Japanese). Retrieved 2025-09-11.
^ abNagasawa, Shigeru (2016-11-24). "「PostPetVR」開発へクラウドファンディング、来年の誕生20周年に向け、原宿カルチャーとのコラボ展開も" [Crowdfunding for "PostPetVR" development, collaboration with Harajuku culture planned for 20th anniversary next year]. INTERNET Watch (in Japanese). Retrieved 2025-09-30.
^Zunko (2025-05-08). "任天堂の社外取締役に『ポストペット』生みの親・八谷和彦氏が就任。平成を代表するメールクライアント、まだまだ名を馳せる" [Kazuhiko Hachiya, creator of PostPet, appointed as an outside director of Nintendo. The representative email client of the Heisei era is still famous.]. Game*Spark (in Japanese). Retrieved 2025-09-30.
^ abcYamazaki, Haruna (2016-11-24). "ピンクのクマがメールを運ぶ「ポストペット」がVRで蘇る。スマホ版も開発？" [Pink bear delivering mail "PostPet" is revived in VR. Is a smartphone version also being developed?]. BuzzFeed (in Japanese). Retrieved 2025-09-30.
^Sekiguchi, Kiyoshi (2003-04-24). "メールアプリ「ケータイポストペット」がJ-SH53向けに登場" [The email app "Mobile Post Pet" is now available for the J-SH53]. Kaitai Watch. Retrieved 2025-09-30.
^"PostPetのWebメール版が9月に登場" [The web email version of PostPet will be released in September]. ITmedia NEWS (in Japanese). 2005-06-23. Retrieved 2025-10-01.
^"懐かしのペットにVRで会える「ポストペットVR」体験会が開催" ["PostPet VR" experience event held where you can meet your nostalgic pets in VR]. MoguLive (in Japanese). 2018-08-16. Retrieved 2025-09-30.
^Serizawa, Takanori (2020-04-03). "「PostPet GO」開発中 メールではなく位置情報ゲームでもなくメッセージアプリで" ["PostPet GO" is under development - a messaging app that's neither an email nor a location-based game]. ITmedia NEWS (in Japanese). Retrieved 2025-09-30.
^"マルチメディアグランプリ'97発表通商産業大臣賞は『ポストペット』に" [Multimedia Grand Prix '97 Announced: The Minister of International Trade and Industry Award goes to "PostPet"]. ASCII.jp (in Japanese). 1997-11-26. Retrieved 2025-09-11.
^ abc"受賞作品一覧" [List of award-winning works]. AMD Awards (in Japanese). Archived from the original on 2004-03-13. Retrieved 2025-10-01.
^"PostPetの生みの親，八谷和彦氏が東京都現代美術館で新作披露" [PostPet creator Kazuhiko Hachiya unveils new work at Museum of Contemporary Art Tokyo]. ASCII.jp (in Japanese). 2010-02-01. Retrieved 2025-09-30.
^TeT (2025-09-26). "想像以上に可愛くて，ちょっぴり切ない「PostPetDS 夢見るモモと不思議のペン」で，ゆったりした時間を過ごしてみた" [I spent some relaxing time with "PostPetDS Dreaming Momo and the Mysterious Pen," which was cuter than I imagined and a little sad.]. 4Gamer.net (in Japanese). Retrieved 2025-09-30.
