My suggestion is to add an additional chat setting. The setting would allow you to disable the private chat feature while on a mobile device.
When accessing torn on a mobile device, if you've previously had multiple chats open it can be annoying when you swap to a tablet or phone as they take up a large amount of the screen.
When all tabs are minimized it isn't so much of an issue, but it would be a nice quality of life update to enable the chat being disabled all together while on a mobile device.
Here is an example of what chat looks like on a mobile device:
[image: puu.sh]
Here are the current settings:
[image: puu.sh]
And finally I modified the code slighlty so that I could show an example of what I'm proposing:
[image: puu.sh]
As you can see there is an additional option at the bottom that allows you to disable the chat when access torn from a mobile device. As I said before it isn't really a "critical update" more of a quality of life update that I believe will be useful for a lot of players.
Hopefully you all like my suggestion :).
E: Additional ideas that could help give more control over chat.
A chat favourites list and a setting where only your favourites can contact you. You could then freely add or remove people to your favourites list without needing them on your friends list. Then you would have four options:
1. anybody
2. anybody you've previously contacted
3. people on your favourites list
4. people on your friends list
Suggestion from nine: Check boxes on the friends list page that allow you to decide which friends can message you and which to "Mute".