Before revision:  The first hugely contentious issue facing the Apps is the deployment framework, i.e. centralised or decentralised . Based on this, the debate branches out to the corresponding technologies that underpin these architectures, i.e. GPS, QR codes, and Bluetooth.
After revision:  The first hugely contentious issue facing the Apps is the deployment framework, i.e. centralized or decentralized . Based on this, the debate branches out to the corresponding technologies that underpin these architectures, i.e. GPS, QR codes, and Bluetooth.