In general, the terms of use describe the following:  

• Purpose of your employee app
• Decide whether the usage should be voluntary or involuntary
• Internal contact person
• Desired communication principles
• Obligations and responsibilities of the user

For informational purposes have a look at the following points that describe the obligations and responsibilities:

By downloading and using the app, employees hereby agree to

• Desist from all measures which could jeopardise the security and stability of the employee app, in particular from accessing information or data without authorization, interfering with the software of the employee app, penetrating data networks of the Provider or transmitting any viruses, Trojans or other malware;
• Only use the employee app in accordance with the purpose outlined above,
• Do not infringe any laws, regulations or other legal provisions while using the employee app, in particular by transmitting content which infringes copyrights, trademark rights, personality rights or other third-party rights and other laws or by creating links with such content;
• Keep user IDs, passwords and other access data secret, do not disclose these to unauthorized third parties, protect these from third-party access with suitable measures in compliance with current requirements and inform the contact person without undue delay if it is suspected that usernames or passwords or other access data could have become known to unauthorized parties.