It is far easier to steal a mobile phone when it is in use or on display. When you are using your mobile phone in a public place try and be aware of your surroundings and anyone that is perhaps standing too close to you. In order to help prevent theft of your mobile phone keep your mobile phone in a secure place on your person or in your bag.
You can also protectively mark your mobile phone, for further information on protective marking please see the question below:
I've heard that the police to protective marking on property, am I eligible?
The police do not need to see proof that you owned the phone or see the phone's box or contract. If you need to find the IMEI/serial number (a number that is unique to your mobile phone) you can do so by typing *#06# into your phone. It can also be obtained from calling your network provider.
See the website in related information which allows you to register free any property with a serial number.
