If you don't want to use the Custom-Keys M1 or M2 at the i.safe Mobile IS910.x you have the possibility to delete the presetting of them.

For doing that please follow these steps

• open App List by swiping from the bottom to the top
• start CustomKey1 or CustomKey2
• choose Null for no Application

Uninstall of this app is not possible and a deactivation require an MDM tool.

Want to know more about MDM tools?  MDM at Wikipedia