How to Control Your Windows 8 Tablet's Touchscreen
Slide your finger on the screen.
Press your finger against the screen; then, without lifting your finger, slide your finger across the glass. When you lift your finger, the item stays in its new location.
Example: To reposition a window across the desktop, press your finger on the window’s title bar — that colored strip along the top edge. Slide your finger to the window’s desired position; then lift your finger to set the window in its new place.