The alarm will only send notifications to your phone when in Bluetooth range. This range may vary depending on what is between the Scout and your phone, i.e. windows, walls, elevation. Orientation of your phone will also have some influence. It is recommended to enable notifications for the Knog app in the iOS notifications settings.
In a free field environment (line of sight) the bluetooth range can reach as far as 60-100 meters. In most instances outdoors, you will see a range of at least 30-50 meters.
Indoors, or in an environment with structures between your phone and the Scout ( for example if the Scout is outside and you are inside), the range will reduce to 10-30 meters in most instances.