What is the cheapest solution for a Project with bluetooth(ble) and light sensor


I am planning on making an arduino setup with bluetooth and light sensor. I want to program the arduino to communicate the light sensor data with my laptop via bluetooth. The arduino should be battery powered.

So what I need is:

  • A simple arduino board
  • light sensor
  • bluetooth module/shield(ideally bluetooth low energy to save battery)
  • battery

What is the cheapest hardware combination with which it’s possible to achieve this?

The 3.3v Mini Pro is about $5. The 5v version costs half that but I imagine the 3.3v would be better for battery operation and the bluetooth module is also 3.3v

just dont do it at all

Why? Please, explain your answer. Tell us the motivations behind this, and the pros and cons of the project of ObiTewodros