08.11.2015 13:00
Viber's minimum requirements are Android 2.3.6 or above. You must also have stable network connection.
If you unable to receive SMS then you need to make sure that you have entered the correct phone number. If you are abroad then you need to turn roaming on.
There is also automatic callback option. If your access code wasn't arrive within 60 seconds, you need to click on "No Code?" or "Press here to get a call" button.