[This article is currently in draft and subject to further updates.]
It seems there is a lot of misinformation circulating about location tracking and battery usage impact for app users. We have heard erroneous generalisations such as “GPS location tracking drains a phone’s battery unacceptably” or “using Bluetooth beacons is much better”.
The extent to which such statements are true or false depends on a number of factors.
The best mobile location data is accurate, frequent, persistent and low latency. At Crowd Connected that is what we deal in. Not limited by proximity to hardware, or limited by the app being in the foreground (i.e. on screen, in use). And not low quality because it is infrequent, imprecise or aged.
Obtaining locations from mobile phones (and sending that data to servers) requires energy. That means battery use. There is no magic solution. We’d question anyone claiming to have some secret sauce!
From time to time we are asked to provide a table of figures in relation to battery consumption. This isn’t practical or even that useful, because every phone is different: model, operating system version, age of device (and therefore health of battery), app installs and usage patterns all vary. Furthermore, on both iOS and Android, battery consumption by app is displayed as a percentage of overall battery usage (i.e. relative not absolute figures).
Experience and know-how
With 100s of deployments of our platform under our belts, we have the experience and know-how to ensure the right balance between battery usage and location data quantity/quality.
We enable the frequency of location updates to be configured. For each specific deployment and use case, optimum settings can be applied.
Our technology is often deployed in environments where people are very battery conscious, like multi-day music festivals. By combining a number of techniques, we ensure we strike the right balance between collecting location data that is fit for purpose (i.e. has the appropriate accuracy and frequency) and battery usage.
How we go about getting a location
We use multiple underlying techniques to determine a phone’s location including GPS, cell triangulation, WiFi and Bluetooth.
What this means in practice: In outdoor environments, the phone’s operating system is likely to provide an accurate estimate of the phone’s location and we can use that in a battery-efficient manner. Indoors - in locations not mapped by Google or Apple - the phone’s operating system will no longer be able to provide a good positioning fix, in which case we use our proprietary Indoor Positioning System (IPS), Sail.
Our Sail technology works by sensing Bluetooth signals from fixed position transmitters around an indoor space. It combines this with inertial (movement) sensing on mobile phones to achieve navigation-ready positioning.
Our solution has dynamic and adaptive settings
The frequency at which we get a location fix from a phone changes, depending on a number of variables. These include the time and location, which can configured via the console's Positioning Configuration module to limit data collection to defined time windows and areas.
Our adaptive data collection optimises every parameter in real-time automatically. Settings vary depending on specific circumstances and use case (i.e. what purposes the data is required for).
What this means in practice: If a phone is a long distance from a place of interest, data collection can be switched off. In this ‘background mode’ battery impact is negligible - in our tests, it has often been difficult to discern the additional overhead. We’re only interested if the phone moves a significant distance.
As a phone moves towards a place of interest, the frequency of data collection can be set at a low rate. Once a phone approaches a defined location (i.e. the venue), the frequency of location fixes may be increased further.
Data transfer has a higher impact on battery life
Our software batches updates on the phone, reducing the number of data transfers. Like other settings, the frequency of data transfers is automatically varied by the system.
What this means in practice: Controlling the frequency of data transfers reduces battery drain. Batching location updates on the phone also has the added benefit that if a phone goes offline temporarily (e.g. because of network connectivity issues) when that phone comes back online we can retrieve the location data from the phone.
There are a number of features of our technology that set it apart from other location tracking solutions in relation to balancing persistent, always-on location tracking with battery consumption.
Put simply, we adjust data collection in real-time to ensure acceptable levels of battery usage in all circumstances. 100s of successful deployments are a testament to this.