Hello client, nice to meet you.
I have a lot of experience in IOT project research and development
I have been involved in hardware research and development for many small sized IoT projects, personal wearable devices, environmental measurement sensors, smart fingerprint locks, Smart water meter, Flow meter... using the ARM platform. cotex, STM32F, TMS320, MSP430, BLE 5.0, Wifi, RF, SIM and are connected via mobile applications (Android & iOS).
I can also make your prototype with cheap price.
Best regards