Visitors - Local phone / burner phone

Transportation, Travel and Trips
1
Family visiting this summer (teenagers).

They have a phone plan at home - but to turn it into an international plan it will be expensive for the time they are here

I'm looking into local sim cards here in Switzerland, but I'm also looking into a "burner" phone --- do they exist here in Switzerland?

There are 3 visitors and I'd like them all to have access so I can let them go their own way and contact them when necessary.

Anyone have suggestions - maybe one of the phone companies is having a sale that you know about.

I have a local sim card but it's for emergency use and Im expecting the visitors will need much more data then I have been using.

I'm doing research now but thought I'd ask and maybe your experiences could guide me quicker.

2
Go with the sim cards. Easy to add more money for data, etc... That is what I use with my kids when they come visit, and they are in University; so pretty heavy data users.

3
yalloswype seems perfect, everything local unlimited, calls + data for just 20 chf a month, no contract and the sim was free, I hope it still is free (no activation costs which typically costs here 60chf per sim)

4
I have done some research on yalloswype --- it doesn't sound like a reliable company/plan.

English forum has a thread as well as trustpilot both show a very unattractive offering / company.