Samsung galaxy S6 is the better smartphone I have ever used. previously I was using Sony xperia z1, z2, z3 but I would say the s6’s camera is far better than the sony z series.
s6 has lots of cool features like IR blaster, fingerprint sensor, heartbeat sensor etc.
Display excellent than anyother smartphone.
Speaker sound Okay.
only cons I faced is the battery backup. rest all excellent . I would strongly recommend Samsung galaxy S6