Kaerutomo

Kaerutomo is a replacement server for Miitomo that is being developed by Kaeru Team in response to Nintendo's shutdown of the original Miitomo service. Most updates regarding Kaerutomo, along with their other services (Kaeru Gallery, and Kaeru WFC), come via announcements by the developers themselves in the official Kaeru Discord server, which is linked on their website.

Miitomo was Nintendo's first mobile app; it released on March 17th, 2016 for iOS devices and May 1st, 2016 for Android. Users could create/edit Miis, make/edit Miifotos, answer questions, customize their Mii's clothing, and more. Miitomo shut down on May 9th, 2018, almost 2 years after it came out.

Important information
 Note:  All of this information was pulled from the official Kaeru Discord Server.

 WARNING:  If you distribute the assets for Miitomo and Kaerutomo without permission, you would be violating copyright laws left and right. We do not recommend you do so. Kaeru is not held responsible for any damage done to your Miitomo app, your phone/PC, and more.

Background
Kaerutomo can be traced back to July 11th, 2018, at least on the official Kaeru Discord server, and possibly further back than that. On January 24th, 2018, Nintendo announced that they would be shutting down their first mobile app, "Miitomo", on May 9th, 2018. Kaeru Team started a project called Kaerutomo to attempt to create a replacement server for the app, in a similar fashion to their work on replacement servers for Flipnote Studio 3D and other experimental projects. Initially the server was only accessible to selected users as part of a closed alpha, meaning that only the developers and certain trusted members were able to access it in its early stages. At the time, the project also relied on Nintendo's asset servers to download Miitomo's files, which were later shut down.

Timeline
Initially Kaerutomo was only compatible with Android devices, with various obstacles in place to iOS support, but in late 2019 / early 2020 the team were able to overcome these and eventually released a tweak to enable jailbroken iOS devices to use the service.


 * On July 12th, 2018, Kaeru Team developer JoshuaDoes on Discord announced that he had rewritten fellow Kaeru developer jaames 's Miitomo asset scraper - such a program would download Miitomo assets in bulk from Nintendo servers to a computer for analysis.


 * On July 22nd, 2018, Kaeru Team developer shutterbug2000 announced "something related to Kaerutomo". His announcement stated: "If you apply this patch to your Miitomo APK (instructions in the .zip, only for Android for now), you'll be able to make Miifotos in Miitomo (only thing that will work, consider this a beta test of sorts)." In the same message, he credited the user Visual Brian for the idea to release a Kaerutomo beta.


 * On July 23rd 2018, shutterbug2000 announced that following a recent breakthrough, "the clothing store will be making a return to Kaerutomo's Miifoto beta", albeit with certain limitations.


 * On July 24th, 2018, shutterbug2000 teased working QR Code scanning support in the Mii editor.


 * On September 16th, 2018, with the help of Discord user Korfi, shutterbug2000 announced that iOS support is on its way, stating: "iOS users! The wait is almost over! We have iOS Miitomo now connecting to the Kaerutomo server. Instructions will be coming once we have everything verified to be working. (Thank you so, so much to Korfi for being my guinea pig with their iOS device :p)"


 * On November 29th, 2018, jaames released an announcement. The announcement reads: "It looks like Nintendo finally shut down Miitomo's asset server, which was responsible for providing all of the content (audio, graphics, language data, etc) used by the app. Miitomo still uses this server even when the Kaerutomo patch is applied, we couldn't set up our own content server because that content is under copyright. … This means that the initial data download for new users will no longer work. Some content which is downloaded as-needed will no longer work either, and this may affect the shop and other parts of the app even for our current users. … We haven't had time to fully investigate yet, so please be patient while we figure out how to move forward from here. :)" Simply put, Nintendo has shut down the asset server Kaerutomo was depending on. This means, that new users cannot access the service any longer, and the shop was heavily affected as well for current users. However, it was noted that archive.org was a valid substitute for the now defunct asset server.


 * On March 23rd, 2019, shutterbug2000 announced that he was able to successfully harness Archive.org as a substitute assets server, although this development required a new patch. His announcement read: "As long as nothing else goes wrong, Kaerutomo will be available to new users once again! New users will need an additional patch to allow downloading the Miitomo assets from Archive.org.".


 * On May 22nd, 2019, shutterbug2000 revealed that substantial progress had been made with a rewrite of the Kaerutomo server code. His announcement read: "Hi Kaerutomo users! Today, Kaerutomo's rewritten server has officially reached the Miitomo initial setup. … I never really expected there would be as many people interested in Miitomo as there are. So, what I was expecting to be a few hundred users at most has grown into over 4000 users in our database (pretty crazy!) As such, we have been trying to get a new, better written server running. … This will allow us to better provide new features, so stay tuned for more updates!" From time-to-time, shutterbug2000 continued to show off progress related to the rewrite, involving questions, wallpapers, floorings, and more.


 * On June 4th 2019, a new Miitomo beta was started, made available as an exclusive perk for donators so as to limit the server's activity and ease debugging.


 * On August 27th, 2019, the progress made on the beta server was released to the public, dubbed the “anniversary” release. This was to commemorate Kaeru’s 3rd anniversary and enabled various features: wallpaper + flooring, friends, Miitomo drop, questions + answers, Miifoto log (to a certain extent), QR code scanning and generating, dates (shop music changes through seasons), etc.


 * On September 28th, 2019, shutterbug2000 teased Kaerutomo running on iOS.


 * On September 29th, 2019, thejsa announced a beta release of an iOS version of Kaerutomo in the form of a jailbreak tweak. Like the initial Android release, this was limited to donators for testing purposes.


 * On January 1st, 2020, shutterbug2000 teased a public iOS release of Kaerutomo. InvoxiPlayGames also teased it as well, saying: "she seems to be inside some sort of electronic device. fruit sticker". The eventual release came 19 days later, on January 20th.

iOS
Kaerutomo is available for jailbroken iOS devices via a so-called "tweak", which hooks Miitomo's code on the fly to patch it as necessary to utilise the Kaerutomo service. It can be downloaded from an APT repository maintained by Kaeru Team.

Jailbreaking is generally considered to be a safe process, although it may affect the stability of one's device and trigger artificial compatibility issues with certain apps whose developers do not allow them to be used on jailbroken devices (such as certain streaming services, mobile games and banking apps).

Instructions on how exactly to jailbreak devices is out of the scope of this wiki page, but the r/jailbreak subreddit on Reddit is generally considered a good source of information and is updated frequently: https://www.reddit.com/r/jailbreak