Despite the fact that until now these two technologies have been used for very different purposes, for some time Wi-Fi signals have been used to gain insights about physical locations, such as retail stores. From this perspective, we are going to compare below the main differences between Bluetooth Low Energy and Wi-Fi.
Most people have in their pockets a mobile phone with the Wi-Fi turned on, which means it is constantly looking for Wi-Fi networks. This active seeking of Wi-Fi networks is used by retailers to detect the presence of customers in the store, or in the surrounding area. Users do not have to manually connect to any network, in fact the whole the process is done without any user intervention.
The seeking of signals is done in the opposite way: Bluetooth Low Energy devices (e.g. mobile phones) are constantly looking for signals of Bluetooth Beacons. When these signals are detected, some actions are triggered in the device - actions such as showing context-aware content (messages, images, etc.) -
The contrast in how both technologies are implemented leads us to a key difference: When retailers are getting information through Wi-Fi signals, they are doing so, even if the user has not given explicit permission. The only option a user has is to completely disable Wi-Fi in their mobile phones. This is an Opt-Out model, and unfortunately, not a very convenient one.
On the other hand, to detect users through Bluetooth Low Energy beacons requires actions from the user: The user has to download an App, and explicitly grant it permission in order to locate BLE Beacons, in a similar way as is done for other location services such as GPS. (Opt-In model).
Marketing on the internet has taught us the importance of respecting the user's privacy, and giving them control over the data they are submitting to companies. However, disregarding privacy concerns, Wi-Fi technology could track more users, as it does not require users to have an App installed.
From a technical point of view, Wi-Fi has not been designed to measure distances between devices, but it is still possible. Although Wi-Fi devices can be tuned to improve the distance precision, it is not possible to change the behaviour of the user's mobile phones, reducing the reliability of the measured distances.
BLE Beacons main functionality is its ability to be discovered by compatible devices, so the distance measures given by these devices are far more accurate, making it possible to get more precise information about the user's behaviour inside a venue.
Wi-Fi requires routers to be configured and connected to an AC power source. Its cost vary greatly depending on the manufacturer, but a high-traffic router runs at least to hundreds of dollars. However, it is possible to use the existing Wi-Fi insfrastructure; in this way costs can be decreased.
BLE beacons are self-sufficient. Actually they can run on a single battery for more than 2 years, no configuration is required in the beacon itself, and its cost is a few dollars per unit.
In both cases it is necessary to plan where the devices are placed and configure their positions in the software driving it.
Almost every single phone manufactured less than 3 years ago has a built-in Wi-Fi + Bluetooth 4.0 chip, so the difference between technologies adopted is not important.
Why should someone want to download an App, and turn the bluetooth on? Well, because users are the ones who actually benefit from the BLE Beacons. They will get very useful information when they turn on bluetooth and come to the stores or venues where beacons are installed. Actually the process is as follows: Users will receive truly useful information and experiences, and in exchange they will allow companies to learn a little bit more about themselves, but never the other way around.
Wi-Fi tracking technology, in fact, does not offer anything to the user, not even internet connectivity due to the fact that they are not required to connect to a Wi-Fi Hotspot in order to be detected.
This is, undoubtedly, the greatest advantage of BLE beacons over Wi-Fi, or any other technologies.