Precautions while using Mobile Phones
Keep calls short since the biological effects are directly related to the duration of exposure. If you must carry your cell phone on you, make sure that the keypad is positioned toward your body and the back is positioned toward the outside so that the transmitted electromagnetic fields move away from your rather than through you.
After for In
I may be able to go after a week.
I may be able to go in a week.Or: I may be able to go in a week's time.
When speaking of a period of time in the future, use in, and not after. Here in means after the end of.