“Technology is best when it brings people together” - Matt Mullenweg

The humble flip phone. Originally a technological marvel, these days seen mostly as obsolete, but seeing a recent modern revival. These devices (popular in the early to late 2000s) helped push forward mobile communication while not demanding your attention every hour of every day. I had a few of these early devices years ago before getting a smart phone. I have fond memories of texting friends long into the night and listening to music on long car rides.

Modern Flip Phones:

Beyond modern day folding phones (which are cool in their own way), modern android powered Japanese and Korean flip phones in particular are gaining popularity with younger generations. These devices are still usable in our modern smartphone ruled world but still respect your time and attention. They also come with both their own unique formfactor and feature sets that set them apart from standard phones.

While these devices cannot do everything that your standard modern smartphone can, that's kind of the point. A more simple device that is capable of modern tasks but one that doesn't steal your attention when you open it to check an email. A modern smartphone will grab your attention and suck you in, even when you simply turned it on to "check one thing".

The Project:

The android system on most Japanese flip phones is quite dated at this point, being based on android 5.1. The default apps and services that come installed on these devices feel dated but still look like they fit on devices like this. I wanted to create a new android system home screen (or launcher) for devices like this that still gives that retro look while feeling modern and providing modern "nice-to-haves".

Natsukashi UI is the name I've decided to name this project. "Natsukashi" is the Japanese word for "Nostalgic". Named after the feeling the project is aiming for, Natsukashi UI is a modern replacement for the stock home screen that comes installed on Japanese flip phones.

The Design:

I designed the interface of Natsukashi UI to be extensible and customizable. The whole app makes use of numbered lists that provide easy access to each option by pressing the respective key on the physical keypad. Transitions between screens are instant giving the whole app a fast fluent feel. When combined with the key based shortcuts and a bit of practice, different parts of the system can be accessed really quickly. For example if you wanted to change the second app in the quick apps page you'd click the apps key followed by 9 > 9 > 1 > 2.

I've also integrated controls for certain scenarios such as when music is playing from the music applet. This adjusts the keybinds on the main home screen to act as music controls, providing the ability to pause/play the music, skip between songs and change the volume all without needing to enter the music applet.

The home screen layout itself is customizable. Many options can be changed within the custom built settings applet from the design of the quick apps screen to the layout of the main home screen. This provides the much needed flexibility that much of the default software on these devices lack.

The Applets:

Natsukashi UI is not just a home screen replacement, but a complete custom UI layer that comes complete with a full set of custom applications (called applets) that come standard with the app. A few of these include a music player, public transit app (exclusive to the Auckland, NZ region at the moment), calendar app, notes app and more to make the whole experience feel more unified.

The app does allow for the integration of your own 3rd party apps such as pinning them to the quick apps screen. Natsukashi UI also has support for integrating J2ME-Loader java based applications and can launch them directly, bypassing the J2ME-Loader home screen.

The Themes:

Because the Natsukashi UI interface is modular, themes are included by default. These themes go far beyond basic dark and light themes as well as simple color themes. Themes in Natsukashi UI completely transform the interface with different graphics and text styles. I'll include a couple of examples of the themes included with the app below.

I also plan to include the ability to create your own theme right inside of the app in a future app update. This will include a full interface that will let you build your own theme consisting of your own fonts, images and colors.

There will be a number of themes included within the app at launch, with more being added over time with new updates.

Benefits:

I think the biggest benefit that Natsukashi UI will bring to these aging devices is speed. The interface feels super smooth to navigate and it feels great to just between different applets with ease. Natsukashi UI also brings a slew of new features within each of the installed applets.

Personalization was a huge part of older technology as well as the early web. Devices and websites used to feel unique by both customizing the hardware and the software of your own devices and profiles. With Natsukashi UI, I want to try and bring some of that software customization back. Rather than avoiding the idea of customization at all costs, I would love to encourage and see users embrace it to make their devices truly become a reflection of themselves.

The Future:

As stated in previous parts of this write up, I do have some plans already for what I would like to include in future updates once the app has launched. Extra built-in themes as well as new applets are going to be worked on throughout the coming months. I'd also like to include a feature to build your own custom theme from scratch.

I would also like to expand the range of tested android versions since at the moment, the app is only verified to run 100% correctly on android 5.1. The only reason for this is that I only have access to android 5.1 powered flip phones. I do plan in the future to get my hands on an android 8 or android 10 powered flip phone to be able to test and optimize Natsukashi UI for those devices.

Please do not be afraid to let me know if there is a theme or feature that does not exist yet within the app that you would like to see. I'm always open to suggestions.

Closing Thoughts:

Natsukashi UI has been carefully designed to be a perfect blend of old and new. I want to bring the best of the old hardware and my new software. This project has been a big focus for me over the past few months and I'm really hoping that upon release, it will make using Japanese flip phones much easier.

Please follow my Twitter(X) and Threads pages for updates on the project.

Thank you so much for reading!