Yes, you didn’t see it coming, but empathy is really important. We are talking about the Next Billion Users here, remember? As developers, we might have the expensive resources like 4G internet to work with but that does not mean that our end users have such. As a matter of fact, there are regions in some part of the world that can only afford EDGE.
Empathy is my way of telling you to carry out some user research. Who are they? Where are they? How best can I reach them? Do they even need all these assets I am feeding them before I can convey meaning? Ask yourself these questions and if you do not have a rigid answer, pick a pen and paper and go for a user research.
You might be shocked that the users you intend to reach to are still using feature phones. In this case, the web and even the mobile web are no longer your arsenals. You might have to start researching IoT, USSD, SMS, etc.