I've been using Twilio to send SMS and things work great. The only issue is that Twilio charges for both outbound and inbound messages. As such, we've been looking for other solutions.
We thought we found it with Plivo as their pricing was more favorable for SMS.
However, with Plivo, very quickly our outbound messages are being marked as spam or something and they're not being delivered.
We are sending the exact same message every day to about 5k users at a given time in the day. The message has a url in it, but it is something our users signed up for.
Two questions: 1. Why does everything work on Twilio and not on Plivo? 2. Is there a code change I can make to ensure our outbound messages sent with Plivo are not marked as spam by carriers and then stopped?