Ok, but with serious issues.

Issue-
Poor usage of background processing leading to reduced battery life. On and off the mountain.

While the app is stable and functions as advertised, it does so at an enormous cost: battery life.
On the mountain it drains so much as to be useless for a whole days skiing.
Off the mountain it continues to drain batteries until the OS actually informed me that this app was consuming too much battery and suggested that I disable background processing.

The features the app offers are a good start, however the app is burdened with an unintuitive user experience and confusing and dated design that is often inconsistent in its patterns.

On another note posting to Facebook appears to be broken.

There are also so many social opportunities that could be leveraged (especially considering the mammoth tourist demographic) but first, please fix these technical and design issues.

MazincaZ about Mammoth Mountain