Opal vs Viber
A side-by-side look at Opal and Viber. For an in-depth review of either product, follow the links below.
Opal
Office & Productivity
Opal is an open-source alternative to Microsoft OneNote for taking notes and organizing information. It allows users to create digital notebooks to capture text, drawings, and web clippings.
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Viber
Social & Communications
Viber is a free messaging and calling app for smartphones. It uses your phone number to connect you with people in your contacts and allows free calls, texts, photos and video messages over WiFi.
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