textra has a large and expanding user base in the world of people who are on-call for data networks. in such a role, 24/7 notifications of varying importance are common. a useful function of the messaging app would be the ability to scan incoming messages for user defined regexp and to perform an action upon detection, the most basic being an auto delete for example (e.g. I know alert X is going to be happening so just auto delete it when it arrives). this feature would obviously require processing resources on the receiving handset but anybody using it would likely be aware of that. this would be an ability slightly less extreme than the "blacklist" option but would definitely be valued by many users. it would have potential additional features as well, such as extending the customisable notification ability to it. example being having notification of a particular colour or sound from a given source, unless the message contains regexp X, in which case use a diff colour or sound. this requires parsing the actual message content so not sure how difficult that is to code. thanks for reading.