Android - Enable Wi-Fi tethering without SIM card or internet connection

I am currently developing an APP to create a communication field between two devices over Wi-Fi tethering and TCP protocols. The first one is an Android device(server) that do not have a SIM card and it is not interesting to the customer. The second one (client) only supports Wi-fi tethering connectivity and needs to connect to an access point or a portable wifi hotspot.
To activate the Portable Wifi hotspot on the Android phone I need to have a SIM Card. However I found an app called FoxFi that allows the phone enable it without SIM Card, but I still need to have some internet connectivity to able to do it (Eg. any wifi connected to a router). The problem is: in the field the customer will not have any internet connect and to get a SIM card is not a option.
Does anyone know how could I force the activation of the Wifi tethering without SIM card and any internet connectivity? 

I believe Hotspot Control does this. Worked for me on Android 4.0.4 on Samsung Galaxy Note (SGH-I1717). It says rooting is usually not required, and it was not required for me either. http://stackoverflow.com/questions/14608833/android-enable-wi-fi-tethering-without-sim-card-or-internet-connection