A new 4-inch Apple iPhone 6s mini on the cards this year?

Last year Apple launched bigger phones, iPhone 6 with a 4.7-inch display and iPhone 6 plus with a 5.5-inch one. Both the phones became very successful and are still selling well. Around Christmas time we heard reports that Apple was working on a smaller sized 4-inch phone dubbed the iPhone 6s...
A new 4-inch Apple iPhone 6s mini on the cards this year?