This section describes the technical infrastructure that enabled the game system to function.
Technically, setting up the sms system was fairly straightforward. Textlocal [23] provide a free messaging service. The game system was developed using their developer API to send, receive and interpret SMS messages. I set up a txtlocal (http://www.txtlocal.co.uk/) account and used their API to send and receive sms messages using PHPCurl. The messages were then passed to a remote SQL database + site hosted for free on 000WebHost (http://www.000webhost.com/).
 |
| Family checking clues sent from a ghost |
This allowed the game system to provide distinct replies to specific text queries. Simple string-matching was used to identify players’ responses, meaning that variations in spelling and lexicon were not recognised. Answers from the spirits were limited in length by the original SMS maximum – 160 characters. The system was deliberately designed to be used by anyone with the most basic mobile phone, so as to be inclusive.
PHP scripts took care of all the logic - depending on which message was received, the ghosts in the machine would send back an appropriate response to the player.
The main difficulty with this sort of application is in designing the game itself. Messages sent by players need to be short and preferably one-word, as the system uses simple string matching to discover what message has been received. Variations in spelling and lexicon are not recognised. Answers from the ghosts are limited in length by typical sms maximum - 160 characters. The system was deliberately designed to be used by anyone with the most basic mobile phone.
