Why does Wi-Fi work for me but not any of my roommates?

I have two roommates that live in the master bedroom, also the furthest room from the router, keep complaining that the internet is super slow in their room.

I've used my devices (Macbook Pro and iPhone 6) in almost every room and I've had no issues.

It's weird because I'm the only one who doesn't have a complaint about the internet speed despite my roommates living in different rooms.

I really don't think it's the router location since my devices work well no matter the location.

What else could it be?

Added (1). The devices that the two roommates are PCs, iPads, iPhones (6), and Playstation 4 so I'm not so sure it's because mine are Apple devices.

That's simple, Macs' RULE!

Have them restart their devices also restart/unplug wait then replug your router/modem

have you tired your devices in their room where they are having issues? Is there a cordless phone or microwave near there? There cause inteference