ApproveIt for Slack - Get approvals in minutes, not days. Right from Slack!
Tragofone - White-label VoIP Softphone with WebRTC and Auto-provisioning
RemoteTeam - Remoteteam.com helps remote teams become great places to work with the fully-integrated platform to automates payments and HR tasks.
PhonerLite - PhonerLite enables your PC to use it for internet telephony (VoIP , Voice over IP, SIP).
Swipes - Plan projects, take action and discuss.
tSIP - tomeko.net/software: SIP client for Windows.