A toy helicopter created from cannibalised smartphones was among the main attractions at a huge toy show in Tokyo on Friday, where producers were targeting the young and the young-at-heart.

The motor that makes a telephone vibrate provides the power for the rotor blades on the Nano-Falcon, which its makers say is the world's smallest radio-controlled helicopter.

The 6.5-centimetre (2.4-inch) machine weighs just 11 grammes (0.385 ounces), has a range of just five metres (15 feet) and can fly for five minutes, but its makers say they are feeding the fantasies of adults who never really grew up.

"Japan's ageing population made us think of developing a toy targeting adults," said Naoki Nakagawa, head of sales at maker CCP.

"Ten or twenty years ago, helicopter-toys could cost a lot of money. Those who couldn't afford it at the time can now make their childhood dream come true at a reasonable price."

The mini machine retails at around 4,700 yen ($50), a price company spokeswoman Kiyoko Hayasaki said came from its use of bits of mobile phones.

"We were able to set the price at this relatively cheap level because we took some key parts from stocks that are widely available in the market for smartphones," she said.

Elsewhere at the exhibition, toymakers were showcasing tablet computers specifically for small children.

"Children like to emulate what adults do, and a survey said 90 percent of tablet computer users let their children use their tablets," said Yuki Itagaki, a spokeswoman for MegaHouse, a subsidiary of major Japanese toy maker Bandai Namco Holdings.

MegaHouse's "tap me" is a tablet specifically developed for use by children aged between four and eight, with built-in parental controls, including a timer that limits use.

"When the timer reaches the set time, the tablet shows a sleeping face instead of turning off," Itagaki said. "Children can't bring tablets to their parents and say 'hey, the power is off. Turn it on please.'"

Despite its price tag of 20,790 yen ($219), MegaHouse aims to sell 100,000 "tap me" in the coming 12 months.

US toy maker Mattel was showing off its Apptivity Monkey, a fluffy monkey designed to hold Apple's iPhone -- and protect it from over-enthusiastic toddlers, who can press buttons on the creature's limbs to create music.

Japan's Takara Tomy has a stand for the iPhone that dances along to the music it is playing.

"We hope adults with a sense of fun like this product," said Tsubasa Tominaga of the company's new products team.

The International Tokyo Toy Show runs until Sunday at Tokyo Big Sight in the Japanese capital's bay area, with Saturday and Sunday open to the public.