Phone line for Businesses or Individuals. Ring4 provides companies with a cloud solution to manage phone lines as simply as they manage emails. The Ring4 work on any iOS or Android device and can be managed via the Admin Console. Ring4 phone numbers are mobile and support unlimited texting, unlimited calling, voicemail and call recording. Ring4 starts at $9.99/month/line.
Burner - Disposable phone numbers -- now with MMS photo support
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Shuffle - One Phone, Multiple Numbers
Rebel Calling - Internet-free international calling for $1 a month
OpenPhone - Simplest way to own a business phone number
Skype for Slack - Move your slack discussions to a group skype call