Parrot, a French company, has been causing a stir with the crowd-pulling demonstrations of its AR.Drone quadricopter. The drone looks and performs like the baby brother of those radio-controlled aerial surveillance drones used by the military. It comes complete with two video cameras installed.

What makes the AR.Drone very different is that it is controlled by an iPhone. Tap the start button on the iPhone screen and the drone is ready to fly. Then simply move the phone up or down, left or right to manouevre the four-bladed quadricopter through the sky.

The makers say it is remarkably easy to operate - even a child could learn to control the drone in a jiffy.

The AR.Drone makes use of Wi-Fi to give it a safe controllable range of 50 metres. This may not sound like much but it's enough for the intended primary use of the drone, which is for playing augmented reality (AR) games. And, what's more, it can be flown indoors.

Just a game

Parrot took four years to develop the drone. The company insists it is intended only for gaming, not for snooping, spying or aerial photography. Under remote control from an iPhone, the drone is designed to kill virtual robots or virtually shoot down other drones.

When the AR game is running, the display on the iPhone overlays images on whatever the drone cameras are seeing. These virtual objects could be digital robots, or they might be beacons attached to friends' drones for AR dogfights.

The drone looks so much like a smaller military unmanned aircraft because it is based on exactly the same type of technology. The price tag will be much lower, though, at a reported £300.

It can fly at 11 miles per hour, remain airborne for 15 minutes after a 60-minute battery charge, explore to a distance of 50 metres from the operator, and it weighs just over 300 grams. It has built-in, automatic flight stabilisation.

Right now the AR game for the drone is pretty basic. However, the AR.Drone runs on an open software platform and Parrot is inviting outside developers to create games for it.

Meanwhile, back on the ground

However much fun it may be to play virtual Snoopy and the Red Baron, the use of phones as remote controls is likely to develop in more pragmatic directions. One such application is the use of your phone as a door key.

VingCard Elsafe, an Indian supplier of hospitality security solutions, has developed technology that lets a mobile phone talk to a lock. This could herald greatly enhanced convenience for hotel guests.

Sanjeev Anand, sales and key accounts manager, India, of VingCard, says the technology bypasses the need to check in and out at hotels, collect room keys at reception or spend time paying bills in the hotel's bars and restaurants. By using near field communication (NFC), your phone will do all of that for you.

Anand adds that two leading mobile companies are already focusing on NFC for just this purpose. Similar technology is currently being used in a few US hotels.

After initial booking and arrival at the hotel, the guest's phone is automatically and remotely loaded with an electronic wallet, encrypted code and hotel room number. The guest can go straight to his room and unlock the door with his phone.

Anand says: "In future, we expect all phones to be NFC-enabled and hotels will have to follow suit to keep abreast."

Mobile remote control for everyone

A number of developers offer remote control software and apps for mobile phones. Many of these apps are intended for remote interaction with desktop computers. Some are highly specialised - for example, turning your phone into a wireless mouse. Others offer a wider range of features including remote system management or running of desktop applications.

Like the remotely controlled quadricopter or the remotely unlocked door, these apps rely on the integration of wireless technology into mobile phones and they tend to be highly location-sensitive.

Apps that connect a phone wirelessly to a computer have to be installed on both devices. For this reason many such apps are available for download directly from the Internet rather than via the phone. They include freeware and shareware, like this sampling from Free Download Manager:

• AgilePresenter 1.03: For the remote control of PowerPoint presentations from Wi-Fi-enabled Phones. It works with iPhone, Nokia S60, N-Series and E-Series, Windows Mobile and Blackberry
• Mobile Witch Remote Control 1.8: More full-featured software for controlling your computer from a distance. It can also produce and run PowerPoint presentations, which display simultaneously on the desktop and your phone. Other available features include selecting or changing tracks, browsing for artists or albums, and volume control in iTunes or Windows Media Player
• OneCable.net Explorer 2.2.0.108: This more technical software makes use of SMS-X10-PC remote control and data logger for GSM data, XLS export, integrated web server and SO counter energy monitor. In addition it offers remote program start from mobile phone via SMS, SMS request for measured values, email on limits, webcam support, and I/O support for Intronico
• Bluetooth Remote Control 2.0: Turns a Bluetooth-enabled mobile phone into a universal controller for Windows. It has features similar to those of Mobile Witch. It also lets the user add or modify controlled programs, and it includes Java and VB scripting

DIY mobile remote control

If you're technically minded and handy with tools, you can modify your mobile phone yourself and turn it into a remote controller. All you'll need are a suitable electronics kit, skill with a soldering ironing and blithe disregard for the warranty on your phone.

Here's what Apogee Kits says about its Remote Control via Mobile Phone Kit MK160: "Remote control by cell phone kit is activated when the backlight of a cellular phone comes on with an incoming call. The cell phone back light needs to remain lit continuously (it should not flash) when the cell phone is ringing.

"Some cell phones or models may be incompatible or may require a different backlight setting for incoming calls. If in doubt, check the manual of your cell phone. To operate this kit, you need a cell phone and a provider subscription or a prepaid phone card. Keep in mind that although there is some protection against unwanted calls, the unit can still be activated by prank callers, wrong numbers dialled, or calls/messages from the cellular provider."

Apogee stresses that the circuit must be used to operate non-critical equipment only. You definitely shouldn't use your home-adapted phone to control a life support system, say, or any application where unintended operation might harm people or damage property.

However, if you get it right, the Apogee kit will let you do many fun things:

• Turn equipment on and off from any location via your phone. For example, switch on the TV as you're pulling into the driveway
• Turn on lighting or heating, open your gate, "simulate your presence", control animal feeders or activate a car alarm
• Use a ring detection circuit to avoid phone charges