Differences between the simulator and the actual device rendering the UI

[FlyBoyJIt]

I recently started developing a very complex clock with multiple shapes being rendered on screen and noticed that some shapes (eve though they show up fine in the simulator) are not drawn on the ionic.

Is this a known bug (these shapes were 2 circles around an arc to achieve a rounded edge) where circled or possible other shapes are not rendered. 

Are there any other known differences (unless this is a memory issue in my code)

[JonFitbit]

There can be differences between the real hardware and the simulator, it's not an emulator.

If you can provide a small example, perhaps we can identify the issue?