I usually receive a list of offers and sometimes there are offers I get for obscure t3 geos like Ghana, Kenya, kazakhstan, etc. the traffic for these countries in popads/popcash is really bad. Even some of the bigger sources like adcash don't have that much traffic for it.
The problem with these GEOs when it comes to volume is the internet infrastructure, many people don't have access to it and even those who do, the quality can be really bad at times. You can still make money in those GEOs anyways, especially with low priced PIN submit offers. But dont expect mega volume in any source, you need to buy it all across the place.