There are a number of people out there who've gone beyond peeking with the corner of their eye to developing new devices in the name of cheating, and it is up for debate whether that's immoral or impressive. Probably, there is a mix of both in there.
In such case, YouTuber Neutrino upgraded his Casio calculator to a smart gadget that has a secret screen, Wi-Fi, and even a messaging functionality. It might look like a normal one; however, don't judge a book by its cover since this one is a very complicated stealthy cheating device that has the appearance of a boring Casio calculator.
Scientific calculators have their limitations; however, this one with a secret OLED screen, Wi-Fi, and a chat function beg to differ.
This isn't any ordinary calculator, and if you needed proof, this Casio fx-991MS' normal-looking solar cell as its turned off is actually is a tiny OLED display. It doesn't stop there, and Neutrino takes the hack several steps further by adding an ESP8266 Wi-Fi module and a rechargeable battery, all the while without modifying the Casio's exterior itself.
The internet connection, while limited, allows it to access text files stored on Google Firebase, and the gadget is activated through a reed switch and handheld magnet. The "button" interface is achieved through magnetic taps and double-taps on a pair of Hall effect sensors.
Moreover, you can actually send text messages, but as you'd imagine, the options are quite limited.
Above all that, this gadget looks extremely normal when its "extra features" are turned off. The magnetic design doesn't let any secrets out, and it still functions as an actual calculator. Because of the OLED, the solar charging is out of the equation, but a LiPo powers the gadget instead.
While the gadget is extremely clever, it is for certain that you wouldn't see it on a "10-second life hacks" video. There is a great deal of time spent on assembling and programming and it is debatable if it was worth it.
If there are people out there that are currently procrastinating and contemplating whether this project is worth it once they go back to school after the quarantine is over, let's just say that actually working for an exam takes considerably less time. But you do you!