Since the Pagtotal has been discontinued, only traditional and foreign options remain:
Boku
Boku is one of the first mobile payment platforms and after searching in a search engine I saw that Brazilian customers (I do not know if it is your focus) can pay with such a system and so I believe it can be viable.
Zong
Zong as Boku was also one of the first systems and I know it is supported in Brazil (if you click on the link above you will see the market share of each of the cellular companies in Brazil.
Payphone
The Payphone entered the market after the two mentioned above and if I am not mistaken was used enough for iOS applications (mainly iPhone) but I do not know how many walks and also can not say if it is accepted in Brazil.
Note: I used Brazil as a reference for not knowing exactly what market you are looking for and as this is the largest Portuguese-speaking country seemed to me to have more chances of being the same.
PS: I don’t know if this question is valid, I believe it might fit in:
Specific practical problems about programming that can be answered.
but I’m not sure.