Not all of us are good at knowing how ripe a fruit or a vegetable is just by seeing it. But the research at MIT has solved this issue. They have created a hand-held device which would say how ripe an apple is based on the glow of chlorophyll in the fruit's skin under ultraviolet light.
The device is 3.5 by 1.5 inches mostly made up of all the commercial objects available in the market making a chip that picks up the fluorescence an exception which the researchers had specially ordered.
The device interacts with the user via the Bluetooth and the android app. With advancement, this device would be able to go for many other fruits and vegetables with dealing with a great amount of data. Read more at : https://www.livescience.com/56040-handheld-device-tells-if-fruit-is-ripe.html