System Requirements

• macOS Sequoia or above
• iOS / iPadOS 18 or above

Some features like Liquid Glass effect are only available on iOS / iPadOS 26 and macOS Tahoe.

Limited Features

As you may have noticed, Umbra Sphere is (obviously) influenced by Fog of World, the pionner of combining the concept of “fog of war” into the real world.

And as a proof-of-concept and one of my side-project, our target is not to become an alternative of Fog of World, but a showcase of another technical possibility (application of S²Geometry).

Therefore, these features are locked by default on iOS and iPadOS:

• Import files with discovery area more than 1km² at once
• Live Discovery

For devices with Fog of World installed, all features will be unlocked automatically for free. Accroding to Apple's policy, we are not allowed to mention that in the app.

Currently, all features on macOS remain free.

Open Source

• Umbreon for Swift: Core components of Umbra Sphere.
• Sphere Geometry for Swift: Fundamental implementation of S²Geometry in Swift.
• Falinks: A command line tool to collect data of administrative regions from OpenStreetMap and Wikidata, and build database and S²Geometry Covers used by Umbra Sphere.