http://www.evilmadscientist.com/2012/resistors-for-leds/
https://i.ebayimg.com/images/g/smEAAOSwNjlefZ9L/s-l500.jpg
Contact the Data Harvest Group Ltd
https://pxt.microbit.org/reference/bluetooth/bluetooth-pairing
Follow this link for an awesome demo of the microbits Bluetooth capabilities.
This was assembled and programmed by a ten year old. The only little difficulty was working out the x and y coordinates to display the labels - Data, Temp: and Light: and the data - in the right places. Trial, error and perseverance got her there in the end.
The micro:bit is connected to the XinaBox, xChip components using a BM02 micro:bit bridge module.
In this example, the light level is being sensed by the micro:bit and the temperature is being sensed by an XinaBox SW01 advanced weather sensor module.
The data is displayed via the XinaBox OD01 OLED Display 128x64 (SSD1306) module.
N.B. No soldering or screwdriver required. The xChip modules click together as simply as Lego bricks, note the small cream coloured XC10 bus connectors used to link the modules.