As far as what runs locally, only DTHs that the company has decided to distribute with the firmware that is given to all customers. At the present time there is no way to load your own code in to run locally or to use any custom code or for that matter any DTHs that the company did not select for universal distribution. They’ve said they’d like to change that at some point, but no timeline.
Since this thread is just an FAQ to list the various device types that do run locally, please take any further follow on discussion about how local processing works or what future features we might like to see to the following thread instead.