Solution for low power RF communication

For my application, I am looking for a low power RF communication device which will be powered on through battery(700mAh Li ion battery). I just want to transmit temperature sensor data wirelessly to an app(windows or android). Also I am expecting the battery life to last for atleast 1 year. Please suggest suitable device for my application.

Bluetooth LE.

See SiliconLabs or Nordic Semiconductor.

both good ideas. Would also suggest looking at 915 MHz FSK chips. An antenna that is directional will let you use smaller RF Transmit power, and hence give you longer battery life.

For minimal battery drain there is the radio transmitter built from a few components. It broadcasts a click every few seconds, depending on temperature. Your receiver keeps track of the time between clicks.

Thread about a similar topic (3 page discussion): "Wireless signal from a tempertaure switch"

https://www.edaboard.com/thread345732.html

can it be recieved by an android phone?

No. Requiring direct reception by a mobile phone without a gateway restricts the protocol choice to Bluetooth. Battery lifetime would strongly suggest BLE with maximum range of 10 m, unfortunately.

Hi, I am thinking of using nrf51822 Soc, can I use this for a range of 5m without external antenna connection?