chatty requests delivery reports, which are expensive
On receiving my phone bill I got a nasty shock. I have a lot of charges for delivery reports for SMS sent via chatty!
Investigating, I found that chatty is requesting delivery reports. I can see this in mmcli, and was able to see that for all messages listed, delivery reports were requested.
These are a chargeable item for most service providers. They are not free.
I have "message receipts" turned off in chatty and have done since I started using it. Having confirmed that this setting is unchecked, I sent a test message, and mmcli confirmed that a delivery report had been requested despite my not wanting it.
Chatty should not be requesting delivery reports if the user does not want them, especially as this costs money for many people. This is an expensive bug.