Link: https://f-droid.org/packages/eu.domob.panoramicon/

Blurb:

Panoramicon is an immersive viewer for spherical panorama images (full 360×180° images in equirectangular projection).

Detail:

As per the README from github.

Example Images

If you're looking for example panoramic images to use with the app, Wikimedia Commons has a large collection of freely licensed spherical panoramas available under Creative Commons licenses. You can browse and download images from:

Spherical panoramas category - A wide collection of panoramas from various contributors

Spherical panoramics by Domob - Panoramas contributed by the app developer

Simply download any equirectangular panorama image and open it with Panoramicon to explore it in full 360° view.

NOTE: Zoom is currently restricted in Panoramicon, so downloading the full-sized images is wasteful. On Wikimedia, the second size down image, should give enough detail. 2560x1280 pixel.

CONTROLS :

Pinch = zoom, swipe = pan, gyro = mlook.