Get crystal-clear nationwide calling for free. You pay only applicable taxes and fees. Connect the Ooma Telo to your high-speed Internet and activate online. Optional advanced features are available with Ooma Premier service including the ability to block telemarketers and other unwanted callers as well as home security.
Features included with the basic calling service:

PureVoice HD technology for clarity and reliability
Integration with Amazon Echo and its voice-enabled smart assistant, Alexa
Caller-ID, call-waiting, call return, 911 and 911 text alerts
Online portal with call log, preferences and contacts
One-touch voicemail audio playback
Remote voicemail retrieval and online playback
Home security for one sensor
Live customer support
Choose any available area code
Ooma Mobile HD app for free outbound calling
Everyday low rates on international calling
Unlimited calling to over 60 countries with the Ooma World Plan
Free Ooma-to-Ooma calling worldwide

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DECT radio supports up to 4 wireless handsets and over 4000 sensors.
A USB port supports Wi-Fi and Bluetooth accessories and provides future expansion opportunities.
Built in speaker provides the ability to screen calls prior to answering.
Built-in 900MHz dual-core processor provides the power for Ooma PureVoice including HD Voice and adaptive redundancy for a more natural sounding voice without stuttering or interruption.