According to the Japanese blog Mac Otakara referring to a reliable source, Apple is being prepared the second installment of a 4-inch iPhone 5s. Apparently, the smartphone is in the production phase, and can occur at any moment. Could this be iPhone 6c?
Most users will probably appreciate the fact if the rumour is confirmed, another 4-inch Apple smartphone will be based on the model 5s rather than 5c. It's rather a good news. According to the authors of the leak, the new iPhone is to be based on Apple A8 processor with WiFi 802.11ac, BT version 4.1 and an enhanced version of FaceTime HD camera with f/2.2. The Japanese have neither a fuller specification or information when specifically the next iPhone would debut.
Source Mac Otokara