app similar to tkcontroller tkconfig

appin both android and ios required to send sms'es to gps trackers for their set-up and configuration to provide an easy to use GUI that relieves the user the need to remember type out long strings of numerals i suggest you look at [login to view URL] and andoid app tkconfig for concept these were created for controlling the tk102 series of gps trackers. i need one for a different brand meitrack VTseries the idea is that it is SMS only no GPRS function there are about 30 different sms commands for example : house battery voltage setting of alarm threshold : the sms command is W000000, 308 ,11.5 this sets the battery low voltage alarm to 11.5 so for this screen using a scroll wheel picker for user to set voltage - then they press a button that says set another button that says off sends the sms W000000, 308, 0.0 - this turns the low voltage function off would require start screens where user inputs their phone number of tracker , their password ( W000000 is default setting - in practice it would be W456789 or whatever 6 numeral combo user selected) reading the manual will show the command structure naturally this will require some back and forth with me - the screens do not need to be fancy just easy to use