The answer is YES. Leaving Bluetooth always on WON'T drain your smartphone's battery, in fact, you will find it super convenient leaving it on all the time, totally carefree.
To put a long story short, Bluetooth technology has evolved to adapt to the ever-increasing use cases. The power consumption of the latest BLE (Bluetooth Low Energy) has been decreased to a level where it consumes very little battery (only 0.01-0.25w)
Everyone has his/her own idea on how to conserve smartphone battery, from turning off notifications to disabling GPS signals. Tons of tips online are telling you regarding how to conserve your smartphone battery, among them, turning off the Bluetooth.
So have you ever questioned yourself? How much battery does Bluetooth consume?
Well, to answer this, we must start from the very root of the problem and find out what is Bluetooth and why do we stereotypically assume it’s battery-consuming.
The notion that Bluetooth drains a significant amount of battery came along with the first generation of smartphones in the mid-90s. It’s hard to tell how many battery Bluetooth consumes in relation to the overall battery capacity, however, what we do know is that along the past two decades, the technology has boomed and evolved in a substantial way.
Comparing the latest model of the iPhone to a 90s mobile phone, the battery capacity has just tripled over the past decades.
And the Bluetooth technology itself has evolved to adapt to consumer needs. Numerous “smart” devices nowadays are invented and connected to the user’s smartphone via Bluetooth.
When Bluetooth was first invented, it was meant to replace cables to transfer data from device to device wirelessly. However, nowadays, the use cases of Bluetooth has been substantially increased, thus the newer generation of Bluetooth-BLE (Bluetooth Low Energy) came into the spotlight.
Bluetooth Low Energy (BLE) was introduced in 2011 as Bluetooth 4.0. The key difference is in the name – the low power consumption. While it’s not the best way to stream music to a speaker or use for phone calls, the BLE protocol is optimized for applications that only need to exchange small amounts of data periodically, for example, location services.
Nearly all smartphones and other connected devices today natively support BLE. BLE consumes little battery while the data transfer speed is relatively lower compared with the Bluetooth (Classic). If your use case is to connect your smartphone with your “smart” devices or for applications to access location data, the battery that these applications consume can be simply ignored.
Most smart devices, i.e. smartwatches or trackers need to be connected to your smartphone all the time to ensure the accuracy and completeness of the data they log. Similar use case applies to the ZUS Smart Driving Assistant app. You might have a slight idea of seeing the prompt saying "Bluetooth is off. Enable Bluetooth so the ZUS app can save your parking location and log your miles."
Needless to say, it’s highly recommended you LEAVE Bluetooth ALWAYS ON if you want to have a smooth & flawless user experience offered by any smart devices. And it's with no doubt that they won't drain your battery as the BLE consumes only 0.01-0.25w with a data transfer rate of 200kbps.