Smartphones carefully track their mobile data usage as most service plans have associated limits and fees. In the example shown, the Data Usage menu contains options for
completely switching off mobile data traffic (that prevents the phone from sending and receiving data over its cell connection but not over a Wi-Fi connection)
limiting mobile data usage (that switches off mobile data traffic only when a specified total usage amount is reached)
setting up alerts to notify the user when total data usage exceeds desired limits
All modern smartphones support Bluetooth connectivity. As shown in this example, Android provides an on/off menu option to control the Bluetooth radio. Consider keeping Bluetooth off when not using it to improve the security of your device.
The Scan button at the top of this menu allows users to re-scan the area for other Bluetooth devices in signal range. Any devices found appear in the list below.
Clicking on the name or icon for one of these devices initiates a pairing request.
Near Field Communication (NFC) is a radio communication technology separate from Bluetooth or Wi-Fi that enables two devices very close to each other to exchange data using very little power. NFC is sometimes used for making purchases from a mobile phone (so-called "mobile payments").
The Android operating system includes a feature called Beam that enables data sharing from apps using an NFC link. To use this feature, first enable NFC, then enable Android Beam via its separate menu option, then touch two devices together so that their NFC chips are in close enough proximity to each other to make a connection - positioning the two devices back-to-back generally works best.
Note that NFC can be used with or without Beam on Android phones.
Cell phones can be set up to share wireless Internet service with a local device network, a so-called "personal hotspot" or "portable hotspot" feature. In this example, the Android phone provides two different menus for controlling the phone's hotspot support, both found inside the "Wireless and networks" More menu.
The Mobile Hotspot menu controls personal hotspot support for Wi-Fi devices. Besides turning the feature on and off, this menu controls the required parameters for setting up a new hotspot:
hotspot network name (Wi-Fi SSID)
network security option (WPA2 or others)
timeout value (that automatically shuts off the hotspot after some number of minutes of inactivity, also a useful security feature)
The Tethering menu provides the alternatives to use Bluetooth or USB instead of Wi-Fi for connection sharing. (Note that all of these methods are technically tethering).
To avoid unwanted connections and security exposure, these feature should be kept turned off unless actively being used.
Also consider these additional mobile network settings, less commonly used but each important in certain situations:
Data roaming: Phones that lose connection to their cell service provider are capable of connecting to other provider's networks while roaming (traveling in and out of the service coverage areas). Android phones provide a menu option to turn data roaming access on or off as shown. Many users prefer to keep roaming off unless they really need it, as using this feature normally results in extra fees.
Network mode: Some phones give users a menu option to choose which types of mobile networks the device will automatically contact. Typical choices include "LTE," "GSM" and Global. Many Android phones use "Global" by default.
Access Point Names (APN) settings: Each type of mobile phone and service uses a collection of network gateway settings. Phones often organize these settings into profiles. Users who move their phone between different service provider networks will need to work with these APN settings.