Samsung Electronics warned its operating profit could fall a two-year low in the second quarter as it grapples with a slowdown in its smartphone business among other challenges - so are the South Korean tech giant's best days behind it?

The company on Tuesday said operating profit for the April-June quarter likely fell 24.5 percent on year to 7.2 trillion ($7.12 billion) on slower smartphone market growth, sluggish tablet sales and a stronger won.