There's other system information you can get from the browser as well
Sometimes you can use this data to see what device/model is being used (although it's trivial to spoof it). In this case, it seems like apple makes it hard to tell exactly which model is being used, so OP is trying to make it easier.
You can also get some information from media queries https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queri...
There's other system information you can get from the browser as well
Sometimes you can use this data to see what device/model is being used (although it's trivial to spoof it). In this case, it seems like apple makes it hard to tell exactly which model is being used, so OP is trying to make it easier.