3 said it expects sales of the INQ Mini to superscede that of the INQ1 handset after it launches in October.
Since November 2008, more than 700,000 Skypephone and INQ1 handsets have been sold.
3 head of internet services David Kerrigan said: “The INQ1 was a big device for us, but the INQ Mini will be even bigger.
“We have great ambitions of what the INQ Mini will deliver.”
The software for the INQ Mini was approved on September 16, and will launch in the first two weeks of October.
INQ has also recently signed a distribution agreement with Singapore network SingTelto roll out the INQ Mini in the country. It is the first non-3 network agreement the company has forged. More are expected to follow.