A smartwatch is a wristwatch with screen and the ability to do much more than tell you the time.They are wearable comuputers,that can run mobile apps, using a mobile operating system. They can be used as portable media players, with FM radio and playback of digital audio and video files via a Bluetooth or USB headset. Some models, also called 'watch phones', feature full mobile phone capability, and can make or answer phone calls or text messages. Smartwatches have an electronic visual display,a rechargeable battery and touchscreen. Peripheral devices include digital cameras, thermometers, accelerometers, altimeters, barometers, compasses, GPS receivers, tiny speakers, and SD card .Software include digital maps, schedulers and personal organizers, calculators, and different watch faces. It supports wireless technologies like Bluetooth, Wi-Fi, and GPS. How do they work?? Watches can cooperate with an app in a smartphone to carry out their functions,for which they
A SIM - short for Subscriber Identity Module - is a piece of plastic that slots into your mobile phone.It acts as your unique ID and helps you connect to, make calls over a particular mobile phone network.Most SIM cards have a capacity between 32 to 128 KB.They store contacts and messages which can be transferred easily from one mobile to another. SIM also stores the ‘key’ needed to decrypt data that is encrypted when voice is trransfered from a phone to another.A unique ID called the IMSI (International Mobile Subscriber Identity) is used to connect someone calling your mobile number to your phone. GSM phones are the ones that utilize SIM cards .The most important bits of data include the IMSI (International Mobile Subscriber Identity) and the authentication key that validates the IMSI. This authentication key is provided by the carrier SIM authentication goes like this: On startup, the phone obtains the IMSI from the SIM card and relays it to the network,known as“request for