Many of my friends and family use Glympse for location sharing and meeting. It has some great features like being able to share your ETA to where you're driving etc.

The Verizon Message+ app supports it but I much prefer Textra. Currently I sometimes have to switch over to the other app when we're using it.

Glympse has an SDK and API @ developer.glympse.com

I would very much appreciate this feature and I'm sure a lot of other users would enjoy it as well. I'd even be willing to make a donation when it appears. Thanks =)