Everyone is familiar with Bluetooth and some of you deal with it on a daily basis. Briefly, Bluetooth is a wireless standard for exchanging data over short distances. It was invented back in 1994 by a telecom vendor Ericsson and has found its way in our headsets and players, keyboards and mice, gamepads, and finally, our phones. But what is actually so great about Bluetooth and how can we use it to develop cool stuff?
Certain Advantages of Bluetooth
- Low energy consumption (especially Bluetooth Smart 4.0 & 4.1)
- It doesn’t matter what type of device is being used for establishing connection.
- Almost all the hitches caused by other wireless devices get eliminated by switching to another frequency.
Obvious Disadvantages of Bluetooth
- Above mentioned universality is relative. The sad truth is, not all adapters support a full list of profiles even though Bluetooth is pretty affordable.
- A bit rate is rather low and ranges from 1 Mbit/s on the version 1.0 to 24 Mbit/s on 4.0 / 3.0. This is okay for small volumes, though.
- A short range of action (no more than one meter for class three, 10 meters for class two, and up to 100 meters for class one). The range of action indicated in the specifications is quite exaggerated, and depends a lot on whether there is an obstacle between pairing devices.
But BlueJacking specialists solved this problem!
BlueSniper is a hacker rifle which is capable of extending Bluetooth radios to 1,78 km using directional antennas and signal amplifiers. Unfortunately, this great solution is a dangerous thing for us, ordinary users. Don’t forget to disable your Bluetooth module when you are done with it. Otherwise, you can make it visible through wireless network, and therefore, open for an attack.
Bluetooth Use Cases
Bluetooth module can be used in a great variety of apps.
In fact, we have already covered some examples of startups that work on Bluetooth. Among them there is PowerUp — a paper plane with a flying device powered by Bluetooth, a digital kitchen scale Pre Pad from the Orange Chef, and a multi-card device called Coin.
- Gloves that have a magic ability to interact with a touch screen and at the same time keep your fingers warm.
- Bracelets that track your heart rate and sleeping phases. A great combination of a bracelet and an alarm clock can adjust to your sleeping cycles (they know it better than you do) and suggest the best time for you to wake up.
- Sneakers that track your activity as you walk, run and even sit.
- Medical sensors, which is a breakthrough for medicine as they can get into your organs instead of tweezers.
- Smart house modules — a must for a new age apartment, which cares about security of home and your personal convenience wherever you are.
- Bluetooth devices can be used to track a person’s health and to prove a health insurance event.
Combination of Bluetooth & Android
Long before Android appeared, Bluetooth had widely been used in other phones, allowing their users to listen to music, share content, play games, chat, and so on. Before Android 2.3. version got launched, Bluetooth support for Android was far from being perfect and couldn’t meet the expectations of owners of popular in those times J2ME and Symbian telephones.
Old Android versions didn’t allow, for example, to use Bluetooth module as a modem, neither did they allow to transfer files (only a small number of Android devices could support OBEX FTP protocol).
The current versions of Android OS support Bluetooth API which offers a broad range of functions which can be used to develop apps of different kinds and purposes. Bluetooth APIs can:
- find other Bluetooth devices within a line of sight
- implement pairing between devices
- set up RECCOM channels
- connect with other devices through service discovery
- transfer data between devices
- manage multiple connections
You can check Android documentation for more information on this subject.
Bluetooth version 4.0 called Bluetooth Smart includes 3 protocols: Classic Bluetooth, Bluetooth High Speed (based on Wi-Fi) and Bluetooth Low Energy. Bluetooth low energy used to exist under the name Wibree. It consumes less energy than the previous versions and developers claim that devices with such chips are able to run for years on a single battery.
Android 4.3 (API Level 18) has a built-in platform support for Bluetooth Low Energy and provides APIs that apps can use to discover devices, query for services, and read/write characteristics.