On Messages for Android, a blue dot or chat icon indicates that the specific conversation or contact you're talking to has ...

Google Messages has replaced text-based indicators with icons for read receipts. Here's how to tell the difference between one and two check marks.

You only have the option to delete a text for everyone if both parties are using RCS messaging. To delete a sent message, long press on it until you see options at the top. Beside the edit button ...