The main difference between these two mobile phones is their dimensions. While the dimensions of Samsung Galaxy S6 are 143.4 x 70.5 x 6.8 mm (5.65 x 2.78 x 0.27 in), Samsung Galaxy S6 Edge has 142.1 x 70.1 x 7 mm (5.59 x 2.76 x 0.28 in). Also, the weight of Samsung Galaxy S6 is 138 g while the weight of Samsung Galaxy S6 Edge is 132 g. Since these parameters are not very clinching, I will choose Samsung Galaxy S6 Edge because it is using a non-removable Li-Ion 2600 mAh battery while the battery of the other device has 2550 mAh.