Before you even think about it, no, this is certainly not the upcoming Galaxy S5, since its model number is lower than the S4’s model numbers (GT-I9500 / GT-I9505). Plus, we’re expecting the S5 to sport a 5.25-inch screen, not a 5.5-inch one. The mysterious device can’t be a new Note, either, because Galaxy Notes have different model numbers: N7100, N9000, etc. So it seems to be a smartphone positioned between the old Galaxy S III LTE (GT-I9305) and the S4 LTE (GT-I9505).
We must mention that Zauba had previously listed other unannounced devices that turned out to be real, including the Samsung Galaxy Note 3 Neo (SM-N7500 / SM-N7505). Thus, more details on the GT-I9405 will likely surface soon.
Perhaps Samsung will officially announce the I9405 at the same time with the Galaxy Note 3 Neo in the near future. We’ll be here to let you know.
source: Zauba via Samsung Updates