The REETLE SmartInk I is a phone case with a touch-enabled E-Ink display and built-in AI features. It features a secondary screen on the back for reading text, viewing notes, recording voice, and displaying to-do items, allowing basic tasks to be completed without using the phone’s main display.
In the back, you have a 3.97-inch E-Ink touchscreen with one-press voice recording, AI-based transcription, summarization, and smart to-do display, all synced to a companion mobile app via Bluetooth 5.0. It supports iPhone 13–17 series and a wide range of Android phones, features a 300 mAh battery with 10W MagSafe wireless charging, and delivers up to 10 hours of reading, 8 hours of recording, and over 2 weeks of standby time. Weighing around 55 grams with a total thickness under 4 mm, it includes military-grade drop protection, tempered glass, widget switching (QR codes, notes, schedules), a thin design, and a 10°C to 55°C operation temperature range, making it suitable for meetings, interviews, reading, journaling, and on-the-go productivity use.
REETLE SmartInk I (ETS 1301 model) specifications:
- Compatability
- iPhone 13 to iPhone 17 series
- Android smartphones (model support via companion app)
- Display – 3.97-inch, 480 × 800, 235 PPI E-Ink touchscreen
- Touch interface
- Capacitive touch panel
- Operated via onboard touch input and mobile app
- Wireless Connectivity – Bluetooth 5.0
- Audio – Built-in microphone for audio recording (up to 8 hours)
- Misc
- On/Off button (supports gestures)
- Record button for recording audio.
- Up to 10 hours of active use
- Over 2 weeks of standby time
- AI Features – Transcription, summarization, smart to-do sync
- Power
- 300 mAh rechargeable lithium battery
- 10W wireless charging for the 300mA battery
- Dimensions − 152 × 74.5 × 12.5 mm (L × W × H)
- Weight − 55 grams
- Operating Temperature − 10°C to +55°C
- Build − Tempered glass, military-grade drop protection
Software support is provided through a companion mobile application for iOS and Android, which handles device pairing, content synchronization, voice recording, and AI-based transcription and summaries. The app is used to configure widgets, manage notes and to-do lists, and push selected information to the E-Ink display over Bluetooth, while the SmartInk I itself operates as a low-power secondary screen without running standalone applications.
The REETLE SmartInk I can record audio non-stop for up to 8 hours in a single session. This assumes sufficient battery charge and no manual stop of the recording. After ~8 hours, recording will stop due to battery limits or internal file limits, and the device will need to be recharged or restarted before recording again. Captured audio is sent immediately to the companion mobile app on your phone via Bluetooth. Once the audio reaches the phone app, the AI processing (transcription, summarization, key-point extraction) happens there or in the cloud, and the results are stored or managed within the app’s data.
Previously, we wrote about the YotaPhone 3 back in 2017, which featured a 5.2-inch E-Ink display integrated into the phone itself, so the concept is not entirely new; REETLE SmartInk I applies a similar idea by implementing it as a phone case rather than a dedicated handset. We have also written about other Android smartphones and tablets with color E-ink displays like the Bigme HiBreak Pro, the Onyx BOOX Tab, and others.
The REETLE SmartInk I is currently available on Kickstarter with worldwide shipping. Pricing for a single unit is $119 US for Super Early Bird backers, $149 US (Early Bird), and $169 US (Kickstarter Special), which will increase to $199 US retail. The product is available in iPhone-specific and Universal variants (for most of the Android phones). According to the project timeline, mass production is scheduled for January 2026, with shipping expected to begin between February and March 2026.
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Did I miss something? How can they have a single model fitting all iPhones from 13 to 17 and another model fitting all Android phones?
Not sure about iPhones, but for Android they offer a Universal Version which looks like a standalone reader device similar to Xteink X4/X3.
The device is still technically in the development phase. Right now, most of the real-world testing and prototypes you see are running on the iPhone 16 Pro.
If you’re looking to grab one, the process is pretty standard for a crowdfunding campaign: you make your pledge now, and once they are ready to ship (expected around February 2026), they’ll send out a survey asking for your specific phone model.
I believe every single model in the iPhone 13-17 range is different from any other, not only in exact size, but in number/position/type of the buttons (notably the action button and the cameral control button), and/or in shape and size of the camera bump (notably on the iPhone 17 Pro which will require a completely different layout).
That’s 20 different models, and each one would require a specific design, mold, tests, certifications, etc. Remember that we’re not dealing just with a chunk of plastic here, but an electronic device with RF, which increases the price of design, prototypes, tests and certification. We’re probably talking at least a thousand $ for each model.
You really need to sell a lot of cases to make that viable.
Having a single MagSafe-attached device (like MagSafe batteries) would make a lot more sense that trying to fit every single model. It seems to be what the “Universal” model is now, but details are sketchy.
It’s also unclear what the wireless charging means:
The REETLE app is also still in development, and Tech reviewers like HansTechTalk and others are already using a beta version of the REETLE app to show off the AI transcription and e-book syncing.
Obvious questions here:
1) How do they plan to accommodate to different phone sizes?
2) Phone case is supposed to be hit, scratched and abused instead of the phone inside. What is the life expectancy for eInk display on that thing?…