The common components found on all phones are:
- A battery, typically rechargeable, providing the power source for the phone functions
- An input mechanism to allow the user to interact with the phone. The most common input mechanism is a keypad, but touch screens are also found in some high-end smartphones.
- Basic mobile phone services to allow users to make calls and send text messages.
- All GSM phones use a SIM card to allow an account to be swapped among devices. Some CDMA devices also have a similar card called a R-UIM.
- Individual GSM, WCDMA, iDEN and some satellite phone devices are uniquely identified by an International Mobile Equipment Identity (IMEI) number.
Several phone series have been introduced to address a given market segment, such as the RIM BlackBerry focusing on enterprise/corporate customer email needs; the SonyEricsson Walkman series of musicphones and Cybershot series of cameraphones; the Nokia Nseries of multimedia phones, the Palm Pre the HTC Dream and the Apple iPhone.
Other features that may be found on mobile phones include GPS navigation, music (MP3) and video (MP4) playback, RDS radio receiver, alarms, memo recording, personal digital assistant functions, ability to watch streaming video, video download, video calling, built-in cameras (1.0+ Mpx) and camcorders (video recording), with autofocus and flash, ringtones, games, PTT, memory card reader (SD), USB (2.0), dual line support, infrared, Bluetooth (2.0) and WiFi connectivity, instant messaging, Internet e-mail and browsing and serving as a wireless modem. Nokia and the University of Cambridge demonstrated a bendable cell phone called the Morph. Some phones can make mobile payments via direct mobile billing schemes or through contactless payments if the phone and point of sale support Near Field Communication (NFC). Some of the largest mobile phone manufacturers and network providers along with many retail merchants support, or plan to support, contactless payments through NFC-equipped mobile phones.
Some phones have an electromechanical transducer on the back which changes the electrical voice signal into mechanical vibrations. The vibrations flow through the cheek bones or forehead allowing the user to hear the conversation. This is useful in the noisy situations or if the user is hard of hearing.