Amazing as a smartphone can be, they can be made even more useful with a range of existing and planned add-on gadgets. Here are four of the best.
This is a wrist watch that connects to an Android phone via Bluetooth. This means the digital watch face can act as a display for your phone so that you don't have to delve into your pockets to check your messages. The features include the ability to see caller ID on incoming calls, check text messages, e-mails, Facebook or Twitter posts, and see what tune is playing on your phone's music player and control volume and song selection. It costs from around £75.
This could be the tech sensation of 2012. It's manufacturers appealed for public funding through a site called Kickstarter and broke all records, raising more than $3.5 million in a week and taking more than 30,000 pre-orders. The device is a watch that works in the same way as Sony's device, but has a Kindle like electronic paper screen that means it can display any image. It's much more customizable and you can even create your own applications: there are tools for runners, cyclists and even a gadget that uses your phone's GPS to tell you how far you are from the flag on a golf course. The device is expected to cost around £100, be compatible with Android and iPhone, and go on sale in September 2012.
This is a more sophisticated version of the running pedometer apps found in many smartphones. Rather than use your phone to track motion, it uses a small sensor that either attaches to your shoelace, or fits in a special slot in the base of some brands of trainer. You can then set custom workouts and get audio time or distance updates as you run, while still listening to your choice of music. The sensor costs around £15 and works with the iPhone or iPod Touch; an extra adaptor will make it work with an iPod Nano as well.
This is something Google is working on, but is very much at the concept stage. It's a spectacles frame that has no lenses, but holds a tiny glass screen in front of one eye. The screen displays information from an attached smartphone such as messages, but means you can still see the real world normally. Suggested uses include "overlaying" Google Maps navigation instructions on your view of the street, letting you take a "photo" of what you can see, or even allowing Skype style video calling. The spectacles also have a microphone built in to allow hands-free conversations or voice command. Sadly there's no pricing or release information available and Google is simply saying this could happen "one day."