Bluetooth Mesh
Features and benefits:
SDK compatible with Bluetooth LE 4.0 / 4.2 / 5.0 
Simple network control and maintenance, which can easily and flexibly add and remove devices in the mesh network. 
 Support USB/UART interface to connect to existing router devices to implement gateway function 
Multi-hop control, all forwarding can be performed through mesh nodes 
Support mesh node OTA (air upgrade) 
Node ultra low power consumption 
BLE chip is certified by Bluetooth Technology Alliance
Development tools:
Schematic 
SEGGER Embedded Studio or Cmake IDE 
BLE protocol stack l Free Android and IOS App reference 
Mesh lighting control and other application references