We assume nobody likes to repeat Wi-Fi password to a bunch of guests. Programmer NicoHood seems to share this sentiment, which explains why he created "Guestwlan". It’s a program that simplifies the whole "share your Wi-Fi password with the crowd" problem.
Guestwlan is made to work on Raspberry Pi with a touch screen. The program itself works whenever a potential Wi-Fi user approaches the Raspberry Pi and requests access to the network. It would then display three separate QR codes, for Android, iOS, and Windows devices respectively.
The three QR codes contain all the information needed for the device to connect to the network. All you needs to do is to scan the code, and the device connects to the local Wi-Fi immediately.
If you have a touch screen Raspberry Pi, try this program out. Get the files on GitHub or at ArchLinux. While the program is configured to use with Arch, NicoHood has mentioned that Guestwlan could probably work in a Debian environment as well.