Introduction: Which is the best indoor positioning technology for mobile apps?

Customers often ask us which indoor positioning system they should use for their iOS or Android apps. The honest answer: it depends. No single technology is best for every scenario. Your environment, use case, and infrastructure all play critical roles in determining the right solution.

You’ll need to weigh the trade-offs between cost, complexity, and accuracy. While “sub-meter accuracy” gets a lot of attention, it’s rarely essential. For most indoor navigation applications, 2–3 meter accuracy is more than sufficient.

Some use cases - like real-time location tracking in the background - present additional technical challenges that aren’t fully addressed here. This article focuses on comparing the technologies available to support indoor positioning on mobile devices.

What’s New in 2025

Bluetooth Channel Sounding (LE Channel Sounding)

Bluetooth 6.0 introduces Channel Sounding, which promises significant accuracy improvements over traditional RSSI-based approaches. Using phase-based ranging (PBR) and round-trip time (RTT), this technology theoretically enables centimeter-level precision.

However, as with Ultra-Wideband (UWB), its practical utility for indoor mobile positioning is currently limited. Channel Sounding demands specific hardware support and suffers from similar real-world constraints - such as line-of-sight and multipath distortion - making it less viable for consumer-grade smartphones in dynamic environments. There are also scalability and battery-life issues to be overcome in real-world indoor positioning use cases. It holds promise, but widespread adoption and integration are still several years away.

Aruba Open Locate

Aruba’s latest innovation - Open Locate - enhances infrastructure-driven positioning. Their new access points (APs) attempt to auto-locate themselves using onboard GPS, with signal timing (FTMs) used to derive locations for non-GPS-enabled APs. However, limitations remain, including lack of multi-floor support.

What’s more significant is the Open Locate initiative, where Aruba exposes AP position data via an open API. This allows mobile apps to retrieve AP locations and use them for device positioning. It reduces setup effort and increases transparency, laying the groundwork for easier integration with third-party indoor positioning solutions. This could be a really significant develpment which we’re watching closely.

The Indoor Positioning Technology Landscape

Positioning Technologies

Bluetooth Beacons

Still the most widely adopted technology for low-cost deployments. When paired with inertial data from smartphones, Bluetooth beacons (BLE) can deliver 2–3 meter accuracy without requiring calibration or fingerprinting.

High-power BLE beacons now offer 100+ meter range indoors, increasing coverage and reliability. Crowd Connected’s solution continues to use BLE plus inertial data for accurate and scalable deployments.

Bluetooth AoA/AoD (Angle of Arrival/Departure) and the new channel sounding remain niche.

This technology is used by Crowd Connected.

Wi-Fi RTT & One-Sided RTT

Wi-Fi Round Trip Time (RTT), standardized in 802.11mc, allows devices to measure distance to APs using time-of-flight. This delivers sub-meter accuracy but is only supported by 30% of Android users - and not by iOS.

One-sided RTT, available since Android 12, eliminates the need for AP cooperation. It works with any AP, but range errors require heavy post-processing and calibration. Accuracy in ideal conditions is typically 3–5 meters.

Wi-Fi 802.11az (Next-Gen Positioning) Still in development, but promising. It shifts positioning back to the AP, leveraging precise time-of-flight for greater accuracy. When finalized, 802.11az could surpass 802.11mc, especially for infrastructure-based systems.

UWB (Ultra-Wideband)

UWB offers impressive accuracy (sub-30 cm), but remains underutilized due to hardware costs, limited support (only premium iOS and Android models), and infrastructure requirements.

In real-world deployments, issues like beacon range, battery life, and scaling complexity often negate its theoretical advantages. For now, UWB is more useful for proximity detection than full-blown indoor positioning.

Ultrasound

Accurate and secure, ultrasound has found niche applications, especially in healthcare. However, costs remain high, and lack of device integration hampers adoption. Sonitor remains the leading vendor in this space.

Techniques to calculate the position

Transmitter locations

If you know the location of all the Bluetooth or WiFi transmitters, then signal strengths can be used to locate the mobile device.

The challenge of this approach is that signal strengths aren’t just affected by distance. They’re significantly affected by the environement, and by dynamically changing factors like how many people are present, and the model of smartphone in use.

Fingerprinting

Fingerprinting is one way of addressing the challenge of varying signal strengths. Every location in a building is visited, and the received signals strengths are measured in a calibration phase.

While enticing due to low infrastructure requirements, fingerprinting still suffers from high setup and maintenance costs. Solutions like IndoorAtlas and Polestar show promise, but consistency remains a challenge - especially across devices and OSs.

Fingerprinting is not a magic bullet. For many applications, hybrid approaches (BLE + inertial) outperform pure fingerprinting in cost, scalability, and ease of deployment.

Self-calibration

Crowd Connected has developed an entirely different approach to dealing with varying signal strengths. A new, patented algorithm is able to continually optimise positioning, dynamically recalibrating as the environment changes.

Summary Table: 2025 Indoor Positioning Technologies