What communication app should we use Groups\Teams or Skype for Business (Skype Call)

I need some advice on what Microsoft communication tool we should move to. We have 150 members of staff in the office, 10 external home based members of staff, and 10 partners we communicate with on a regular bases.

We want to move to Office 365 Groups and MS Teams but we also need an app that can make calls (like Skype calls). We wanted to make it as simple as possible for the members of staff and only use one communication application.

We are also moving to SharePoint online for our document and records management (DLP, Records Management, Retention Policies...), so do not want three new apps for members of staff to learn. We would prefer two new apps (one Communication app and one Document Management app).

Does Office 365 Groups and MS Teams have a call feature like Skype calls? If not can we add Skype to Office 365 Groups and MS Teams?

Company Communication:

• Office 365 Groups and MS Teams
• Skype for Business (Skype Call)

Document and Record management

• SharePoint Online (DLP, Records Management, Retention Policies...)