It's nice that Samsung brought back the microSD slot, but for the dual-SIM versions of the Galaxy S7 and S7 edge things haven't changed really - the hybrid slot means you can have either two SIMs or one SIM + one microSD, never three cards at once. You know what they say, never say never. With some scissors, a lighter and a lack of caring, you can do this ill-advised hack - if a microSD and nanoSIM can't fit in the same slot, you make them fit. How to fit a microSD and nanoSIM in one slot or ruin both I'll leave you to read the gory details over at NoReplied.com, but...
Source: http://www.gsmarena.com/mod_solves_galaxy_s7s_hybrid_slot_issue_fits_three_cards-news-17365.php
