How to Enable Teams Walkie Talkie feature | Office 365
Turn on or Enable the Walkie-Talkie app in Teams to have instant push-to-talk(PTT) communication for your team.
Walkie Talkie is supported on Android devices with Google Mobile Services (GMS) and iOS devices
Walkie Talkie is not pre-installed,
Step 1) go to Teams Admin Center
Step 2) Teams Apps
Step 3) Setup Polices
Step 4) "Allow user pinning"
Step 5) Add Apps
Step 6) Search for Walkie Click Add
Step 7) Save and wait up to 48 Hours.