People have been doing some stuff in this space in the past, the best like “I’m Ok” are focused on smartphone users, but we have a need to make it work for even the simplest phones. 
Watu wamekuwa wakitumia njia zinazofanana na hili tunalolisema tangu siku za nyuma, kwa mfano watu wanaotumia simu za kisasa (smartphone) wanaweza kutumiana ujumbe wa "niko salama", lakini inabidi hilo liwezekane hata kwa simu za kawaida sana.