TL;DR: The forever-useful Texas Instruments TI-84 Plus graphing calculator is on sale for $ ... or tan — there's a button that does it for you. The LCD screen could definitely use a color HD ...

You can leave the TI graphing calculator at home thanks to this web-based TI-83 and TI-84 emulator ... The image of the calculator has working buttons and will show the boot screen just like ...

[Owen] got down and dirty by adding a touchscreen to his TI-84 graphing calculator ... commands are sent through the UART, and the calculator program draws on the screen. Adding a touch screen ...