Add E Ink and AI to Your Phone Case With the SmartInk I

Most phone cases do one thing and one thing only: protect your phone from damage caused by drops and scratches. The REETLE SmartInk I does all of that, but it also adds an E Ink display and one-touch voice recording capabilities to boost your productivity. These extra features are packed into the case without adding significant bulk — the SmartInk I is just 4mm in thickness.

The main idea behind SmartInk I is to turn the back of your phone into active, functional hardware instead of wasted space. Nearly the entire rear surface of the case is covered by a low-power E Ink display that remains visible even in bright sunlight and consumes minimal energy. This screen can show persistent, glanceable information such as calendars, to-do lists, boarding passes, QR codes, or AI-generated summaries, all without needing to unlock the phone or drain its main battery.

There is also a dedicated physical record button integrated directly into the case’s frame, enabling instant voice recording with a single press. There’s no need to open an app or navigate menus, which makes capturing ideas, meetings, or spontaneous thoughts fast and frictionless. Audio is sent to the companion app via Bluetooth or Wi-Fi, where AI tools transcribe the recording, extract key points, or generate structured to-do lists. Those summaries can then be pushed back to the E Ink display, creating a closed-loop workflow where information is captured and reviewed using the same device.

REETLE managed to keep the case just a few millimeters thick by reducing the battery to under 1mm and the display module to around 1.5mm, all while maintaining structural integrity. The case includes corner guards, tempered glass, and a military-grade protective build designed to withstand everyday drops and scratches. The case supports MagSafe passthrough charging, allowing both the phone and the case to recharge without removing it.

Power is supplied by an internal battery rated for up to 10 hours of continuous reading or recording, with a standby time of up to seven days. This ensures the E Ink display and recording features remain available even when the phone’s battery is running low.

The SmartInk I is controlled through a dedicated mobile app that handles device management, updates, transcription review, and widget customization. REETLE is also aiming for broad device support, with versions planned for multiple iPhone generations as well as a wide range of Android phones. The SmartInk I is currently being offered on Kickstarter, with rewards starting at about $120.