Max Shutter speed
Panasonic GX7 can shoot continuously at max speed of
5 fps and has max shutter speed of
1/8000 sec. GX7 also has an electronic shutter which can shoot silently at max speed of
1/16000s. One thing to keep in mind is that electronic shutter may cause rolling shutter / jello effects, and also banding issues under artificial light on your images.
Flash
GX7 has a built-in flash, and it also has a flash shoe to mount your external flashes too.
Focusing
Panasonic GX7 features a Contrast Detection autofocusing system. The AF system has 23 points to choose from.
Panasonic GX7 also features
Face detection AF where it intelligently detects the faces in the frame and locks the focus automatically.