Image Viewer
On-device image viewer
Photos and animated GIFs decoded entirely on-device, strictly read-only. Nothing is written, nothing leaves the device.
Last updated Jul 2026
On-device file browser
Overview
Image Viewer opens photos and images directly on Passport Prime. It browses all three storage locations, Internal, Airlock, and USB, showing just folders and images, and decodes PNG, JPEG, GIF, and BMP on the device itself. Images are scaled to fit the screen, tall images support drag-panning, and animated GIFs are decoded frame-by-frame and played on-device. Previous and next move between the images in a folder rather than pages of a single file.
The app is strictly read-only. Its signed permission manifest contains no write grants, so it cannot modify, create, or delete anything. Passport has no network stack, so decoding happens entirely offline with no cloud and no companion app, and images never leave the device. A corrupt or mislabeled file shows a clear error banner and the app keeps running.
What it does
- Decodes PNG, JPEG, GIF, and BMP entirely on the device.
- Animated GIFs decoded frame-by-frame and played on-device.
- Browses Internal, Airlock, and USB storage with folder navigation.
- Previous and next flip through all images in a folder.
- Images scaled to fit, with drag-panning for tall images.
- Strictly read-only: the signed permission manifest holds no write grants.
- Offline by design, since Passport has no network stack.
Technical breakdown
How the proof-of-concept is built, for developers evaluating the platform.
On-device decoding
PNG, JPEG, GIF, and BMP are all decoded on the Passport itself, scaled to fit the screen with drag-panning for tall images. Animated GIFs are decoded frame-by-frame and cycled on-device.
Read-only by manifest
The app signed permission manifest contains no write grants at all. It can read files across Internal, Airlock, and USB storage but cannot modify, create, or delete anything.
Offline and resilient
Passport has no network stack, so images never leave the device: no cloud, no companion app. A corrupt or mislabeled image shows a clear error banner and the app keeps running.
Dig into the source
README, architecture notes, and the wire protocol live in the repo.