Skype for Slack - Move your slack discussions to a group skype call
Arvia for Slack - Start quick video calls in Slack channels.
Aircall Now - Make voice calls inside Intercom Messenger 📞💬
Moon Dialer - Use free voip & wifi calling app for unlimited international calling. Moon Dialer is one stop solution for call recording, call scheduling and call forwarding.
HandsFree 2 - Call and SMS in Mac using your Android phone via Bluetooth
Viber - Free and secure calls and messages to anyone, anywhere. Keep your conversations going no matter where you are.