In India and certain other regions of the world, Samsung sells the Galaxy S7 and Galaxy S7 edge with a hybrid SIM card slot that makes it possible to use either two SIM cards or one SIM card and a microSD card on the phone at any given time. This is a bummer since many people would have really liked to use two SIM cards and a microSD card on the phone.
As they say, where there is a will, there is a way. A Galaxy S7 user, who was bummed about the lack of proper dual SIM functionality on his Galaxy S7, has managed to come up with a mod to recognise two SIM cards and a microSD card at the same time. The process requires a bit of DIY job, but if you are up for it, you should be able to enjoy the benefit of having two SItM cards as well as a microSD card on your Galaxy S7 or S7 edge. The process involves taking your secondary nanoSIM card and cutting it down to the bare essential. The process is definitely risky, but if you end up damaging the SIM card, you can always get a replacement SIM card from your operator shop. Then, you need to glue the SIM card to your microSD card and place it on the SIM card tray very carefully. Proceed to insert the SIM tray into the phone and voila! Your Galaxy S7 or S7 edge should be recognising two SIM cards and a microSD card now.
Obviously, since the microSD card is now glued to the SIM card, you cannot easily insert them in another phone. But if you plan on using the Galaxy S7 or S7 edge for the foreseeable future, this hack makes perfect sense for you. You can find a step-by-step guide through the whole process at the source link below, so do make sure to check it out. Do note though that this hack will only work on those Galaxy S7 and Galaxy S7 edge units that ship with a hybrid SIM card slot.