I'm working on a project that will require me making phone calls these days to Japan, Germany, Russia, USA. The calls are part of my ongoing research to acquire information on how science taught in western countries, especially in the above mentioned countries. I will be calling several schools in Japan, USA, Germany, Russia. I'm sure it would take long talk times. I just want to see how I could cut down on call cost as my emails to several schools didn't get a response yet.

Already bought a GLO SIM card and was trying to subscribe to GLO "overload" but just discovered the bonus is only for GLO to GLO calls or SMS. Also it just work between 10pm to 8am, so wouldn't work for me.

Does anyone know of any phone network that allow it's bonus for international calls?. If yes, I'll like to know the network name/promo name and how to subscribe.
Thank you all.

no

seun, lalasticlala.
I'll appreciate if you can help me get this topic on FP so I could get answers today because of time. Please....