I second the comment about working with Hubspot as we don't really use the Sakari interface at all, it's all run through Hubspot

So technically SMS doesn't support read receipts. What you are probably interpreting as read receipts on your mobile are actually coming from either iMessage(Apple) or RCS (Android) which are effectively layers over the top of SMS that do support it. We are looking into support RCS later this year, especially as Apple has recently announced they will begin supporting RCS.

Yeah that would be useful, and also if you can make this work with Hubspot integration as well

This would be a great feature.