How can I lock my sim card (so that nobody can reach me) but keep my iphone4 on? Do I have to switch off the phone first and switch it on again without activating the SIM card? Or is there a short cut? Thank you.
I think you're looking for Airplane mode. It turns off cellular connections so that calls, texts and 3G/4G/LTE are cut off. You can still turn on Wifi while in Airplane Mode.
