Why SMS?

Drivers stranded in nature reserves will seldom think to load a rescue app before starting their journey, or even know which one to choose if they decide to do so. And breakdowns often occur in remote areas where cellular network coverage is slow. The SoS SMS service needs to be as simple and fail-safe as possible.

SMS text messaging is built into every cellphone, does not need to be installed before use, and indeed cannot be uninstalled. It is the only messaging service that is always available. Hence the SoS SMS apps use it as the default means of communication. They can also offer WhatsApp as an alternative, if the rescue hub enables this option. The charge per WhatsApp is generally less than 1% of that of an SMS, for those that are concerned about costs.

The SoS SMS service uses short messages to move information between apps in order to minimise bandwidth requirements.

The stranded driver's SoS SMS app and the rescue driver's SoS SMS app are delivered as a progressive web apps (PWA). They do not have to be pre-installed. They will load into a standard browser page when first referenced. Installing a copy on the user's phone is optional.