Ever thought of charging your phone while cycling? Well, Nokia has.

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The world's top mobile phone maker Nokia on Thursday released details of four new cheap phone models and a battery charger powered by the energy generated from riding a bicycle.

The charger, which can be fitted into any Nokia phone with a 2 mm charger jack, uses a dynamo to generate electricity from the movement of the wheels, Nokia said in a statement.

"Bicycles are the most widespread means of transport in many markets around the world, so this is just one more benefit to be gained from an activity people are already doing," Alex Lambeek, Vice President at Nokia, said in the statement.

The price of the charger kit, which also includes a holder for securing the phone to the bicycle, will vary according to market, but in countries like Kenya, where the product was introduced Thursday, it would be around 15 euros (18.43 dollars), a Nokia spokesman told AFP.

To begin charging, a cyclist needs to travel around six kilometres per hour (four miles per hour), and while charging times will vary depending on battery model, a 10 minute journey at 10 kmh produces around 28 minutes of talk time or 37 hours of standby time, the spokesman said. The faster you ride, the more battery life you generate.

The charger is set to become available through selected retailers and the company's online store before year-end, Nokia said.

The four new phones it also introduced in Kenya Thursday target developing markets, a key growth area for the Finnish company, and also contain features designed for the needs of people in countries where access to electricity is limited, such as a six-week battery standby time.

Shipments of the phone models, priced at 30-45 euros, will begin by September.