Android Based POS system

Design and implement an Android based POS system to connect multi located food kiosks to control cash sales and inventory reports only. No bar code scanning nor credit card transactions required. All tablet / store locations can be accessed from anywhere by Internet and can operate as standalone if the Internet service is interrupted and can recover and reconnect as soon as service is restored.. Total current product lines to 20 items only but scalable for future expansion. Must evaluate and recommend the hardware and data connection service. Will need a 7 or 9 inch tablet, receipt printer without cash box,operating manual and Internet connection. Detailed requirements / wish list available.