You could also press a button to speak into the app which would transmit the sound of your voice to the other device in the child's room.
If more gadgetry appeals to you, Audiovox is working on a G.R.M.S.-compatible model that will also have a built-in Global Positioning System tracking device and an emergency button to transmit your location to other Audiovox G.P.S. radios.
Luke Crawley, assistant general secretary of Bectu, said: "People at the BBC very rarely go on strike and with many shows being pre-recorded all that is needed is a manager to press a button to transmit it.
No investor you'd want is searching through a database and pressing the "Send Now" button to transmit money.
I'm testing the game on PlayStation 4, which you'll know has a handy Share button for transmitting screenshots into the Twittersphere and elsewhere for pals and pricks alike to gawp at.
Yes, the main function of these apps does mimic a walkie-talkie: You press down a button and immediately transmit a voice message to a friend.
Another knock: This app doesn't transmit your utterance until you release the Talk button, so it's slightly less real-time than its rivals.
What if, for example, a crew member of the first plane to hit the World Trade Center had been able to press a panic button, and begin transmitting those video images to the authorities on the ground.
So they designed a battery-operated weight that can detect and display the user's pulse rate, and can transmit an infrared signal from buttons on the handle to "an entertainment device, such as a television, radio or videocassette recorder, or an exercise device, such as a treadmill, a stair-climbing simulator or a resistance machine".
And in the next couple of years, vehicle manufacturers are also going to be required to install emergency call buttons, which will transmit GPS signals and have the potential to use telematics.
