The Samsung Galaxy A7( 2016) is essentially an A5( 2016) stretched to 5.5 screen size. This sort of size has turned into somewhat of a sweetspot for a phablet - any bigger and the phone becomes unwieldy, any smaller and you lose the benefit of the big screen .
While the A5( 2016) competed with the company’s flagship - the Galaxy S6 - the A7( 2016) is placed somewhat differently - it can’t even hope for taking on the Galaxy S6 edge+ or the Note5, so it’s instead targeting a market populated by a number of Chinese-made phablets