CODEWITHSUNDEEP
androidbluetoothbluetooth-lowenergyandroid-bluetooth
Cinedine
Cinedine

Reputation: 23

Android - Detect if other users of my app are nearby

I'm working on an Android app that needs to detect if other users of the app are close to each other (lets say within the same room or Bluetooth range). The app needs to be able to detect this without any user interaction.

My idea is to detect if users are within a close distance of eachother by periodically Bluetooth scanning and checking the results against a list of MAC adresses that contain all the devices that have the app installed. The MAC adresses of all devices are send to a server, the devices then grab this list of mac adresses from the server to compare to the results of a BT scan.

Problem is, BT and Google's seem to use Advertisement / Discovery patterns where one device acts as the server and one device acts as the client. For this to work properly i feel like the devices need to always be discoverable.

Will an implementation based on Google's Nearby or BT work for my needs ?

Is it possible to detect the presence of a nearby device without it being discoverable ?

As battery life is a concern (need to be able to do this for atleast 8 hours a day) is BLE an option?

Upvotes: 2

Views: 2298

Answers (1)

RBusarow
RBusarow

Reputation: 754

You can almost certainly handle 8 hours a day if the phones aren't really used for much else. There are a lot of variables, however.

Many older phones require a different type of scanning using infinite scanner restarts in order to properly report "seeing" a peripheral. This can dramatically decrease battery life.

If the phones are running Marshmallow or later, they have a doze mode which interrupts scanning. This can be circumvented using an AlarmManager, JobService/Dispatcher, or WorkManager. This can dramatically decrease battery life.

If the phones are running Oreo or later, they require a foreground service (persistent notification) in order to prevent the app from being automatically killed by the OS to save battery. The app should also be whitelisted from battery optimization because even with the foreground service, the app will still be killed off by the OS.

Finally, scanning and broadcasting and using location services is pretty expensive battery-wise. If you're attempting to cluster phones and guess their position based upon what other phones are nearby, at some level you'll still need the location data off of the phones to figure out where they're at.

You're much better off just scanning. You could carpet your company property with beacons, where each individual beacon's location is recorded. When the phone "enters a region" (comes within range of a beacon), it should send something to your api reporting which beacon it just found. This will tell you what room/area it's in.

Another less flashy (and potentially less accurate) way to track everything would be via the IP addresses of the wireless access points they're connected to. Use a WorkManager to periodically update an api with some unique ID for the phone and the IP address of the AP. Your IT department should know the locations of each of them. This way you get reasonably good tracking and virtually no battery drain.

Upvotes: 2

Related Questions