calling apps

[nwankomblesse]

I've come across loads of different solutions, BUT Viber only allows me to call other Viber users and my moms in Cameroon doesn't own a smartphone. Skype is nice but actually pretty expensive.

I've seen some voip aps but it's pretty hard to find my way here.

What are some good solutions to save money on my calling charges to Cameroon and Germany? I'm currently in the Netherlands but often reside in Glasgow.
What are the best calling apps and which ones offer good rates?

Thanks all!