Message delivered: When you send a message via mysms friends we automatically send a free delivery report.
Message not delivered: If you notice a red exclamation point next to a sent message, this means the message could not be delivered. There are several reasons for this, e.g. your contact has turned off his mobile phone or has bad or no reception.
Lock message: If you lock a message, it won't be automatically deleted even if you activate auto-delete in the settings. However, if you delete a whole conversation, locked messages will also be erased.
Delete message: Click on the recycle bin to delete a message or a whole conversation.