Hm, not sure I follow… you can fully automate it, eg. taking the picture from the doorbell, when someone rings and then take required actions. Eg. take a look on Face++ ([APP] FACE++ Face Recognition for Homey) etc.
But question about Homey Netatmo App can be answered either in the thread directly ([APP] NetAtmo by Athom - #224 by Sharkys) or by Athom (via support).
You may also want to take a look on Netatmo forums : Netatmo Forum - Security Cameras and accessories (ENGLISH)
