After a lot of updates and works on the Web-App, I was able to give a great features to Android phones.
After releasing the Live Tile for Windows:
https://www.microsoft.com/store/apps/9NN531W4KWW8

I wrote also an Android widget:
https://play.google.com/store/apps/details?id=com.sscheduler.Viewer.Android

After installing it, you have to insert your calendar ID and friends code. Then you will get 1 to 5 icons on the main screen with the next shifts.

Want new features?

If you need some features, write it here. I will try to implement them as soon as possible.