VPS vs GPS: how visitors find their way once they walk indoors

VPS vs GPS is the question to settle before you promise visitors turn-by-turn directions inside your building. GPS gets people to your parking lot; a visual positioning system (VPS) is what can guide them from the entrance to the right store, ward or gate.

Key takeaways

• GPS needs open sky; inside large buildings it drifts and cannot tell floors apart.
• A VPS finds the phone's position and heading from the camera and a 3D map.
• VPS needs the venue mapped first, and the map needs updates after fit-outs.
• Most venues combine both: GPS to the entrance, VPS inside.

This article is for property, marketing and facility managers of malls, hospitals, campuses and other large venues. You will find a plain comparison, a step-by-step guide to how the two technologies hand over to each other, what to measure, and where VPS still has limits.

What is the difference between VPS and GPS?

GPS estimates position from satellite signals and works best under open sky. A visual positioning system, or VPS, estimates position by matching what the phone camera sees against a 3D map of the place. GPS needs no map but loses accuracy indoors; VPS needs a prior map but works where satellites cannot reach.

In practice, the comparison looks like this:

	GPS	VPS
Signal source	Satellites	Phone camera
Needs a venue map	No	Yes, a 3D map
Works indoors	Poorly	Yes, where mapped
Knows the floor	No	Yes
Knows the heading	Roughly	Yes, from the image
Venue hardware	None	None

A VPS works by relocalization: the phone finds its exact place in the map from a single camera view. Because the answer includes orientation, AR arrows can be drawn on the actual floor in front of the visitor.

Between two relocalizations, the phone tracks its own motion with its sensors. The VPS corrects any drift each time the camera sees a known part of the venue.

The key point: VPS does not replace GPS. It takes over where GPS gives up.

Can GPS work indoors in a shopping mall?

GPS can sometimes give a rough fix near entrances, skylights or glass facades, but it cannot be trusted inside a shopping mall. Roofs, concrete floors and steel structures block and reflect satellite signals, so the blue dot drifts, jumps between corridors and never knows which floor the visitor is on.

For a visitor, this shows up as small, frustrating moments:

• The map shows them in the wrong corridor.
• Directions point to a store one floor up as if it were next door.
• The route recalculates every few seconds.

The causes are physical, so a newer phone does not fully fix them:

• Blocked signals. Roofs and floor slabs absorb most of the signal.
• Reflections. Steel and glass bounce signals, so the position jumps.
• No floor information. GPS has no reliable way to tell level 0 from level 2.
• Weak heading. The compass is easily confused by metal structures.

Phones also blend Wi-Fi and cell signals into the location they report. That helps in some buildings, but the result depends on infrastructure you do not control. If you want reliable mall wayfinding, you need a positioning layer designed for indoor spaces.

How to combine VPS and GPS in 5 steps

The steps below are general recommendations for a shopping mall. Only step 1 draws on a real case: the mapping of Città Fiera in Udine, Italy, our latest shopping centre deployment.

1. Map the venue. One operator captured Città Fiera (150,000 m² GLA, 230+ stores, multiple floors) in about 90 minutes with one 360° camera, during opening hours. The result is a metric 3D map used for positioning.
2. Pick the handoff points. Choose where GPS ends and VPS begins: each entrance and each parking garage exit. A QR code there only opens the web link.
3. Keep the outdoor leg simple. Link the venue address to the visitor's maps app. Do not rebuild what GPS already does well.
4. Relocalize on arrival. The visitor points the phone camera ahead, the VPS finds their position and floor, and AR directions start in the browser.
5. Plan floor changes and updates. Route through elevators for accessibility. Re-capture zones after major fit-outs so the map matches what the camera sees.

How do you measure indoor navigation success?

You measure indoor navigation success by tracking whether visitors get a position quickly, finish their routes and change behavior afterward. The core metrics are first-fix rate, time to first fix, route completion and drop-off at floor changes, compared against a baseline recorded before launch, plus business outcomes such as time on site.

Agree on these definitions with your team before launch:

• First-fix rate: share of sessions that relocalize at the first attempt.
• Time to first fix: from page open to the first AR arrow.
• Route completion: share of started routes that reach the destination.
• Floor-change drop-off: where visitors abandon multi-floor routes.
• Business outcomes: time on site, conversion, help-desk questions.

Record the baseline before launch, because every venue differs. Beacons, printed directories and staffed desks remain valid options, and many venues keep them alongside a VPS.

What are the limits of VPS?

A VPS only works where the venue has been mapped, and the map ages as stores, decor and layouts change. Recognition is harder on long blank walls, glass, very low light and dense crowds. Visitors also need to hold the phone up for a moment, which not everyone is willing to do.

What this means in practice:

• The map ages. Plan re-captures after fit-outs and seasonal decor changes.
• Low texture. Test long corridors and glass facades during mapping.
• Darkness. Check service areas and parking levels with low light.
• Camera use. Offer a 2D map as a fallback for visitors who prefer it.

None of these limits is a reason to avoid VPS. They are reasons to test before launch and to budget time for map updates.

Which VPS works in the browser without an app?

A browser-based VPS runs through WebXR, so visitors open a web link instead of installing an app. OVER, a spatial computing company based in Udine, Italy, offers one: the phone camera relocalizes against a 3D map of the venue in under 100 ms with centimeter-level accuracy, indoors and outdoors, with no beacons or markers.

OVER's visual positioning system (VPS) runs in the smartphone browser, and the platform counts 270,000+ locations mapped. For venues, the same 3D map powers AR navigation on visitors' phones, the interactive map on the venue website and on-site kiosks.

At Città Fiera, OVER's CEO reported in October 2026 that time on site rose 25% and conversion rate rose 12%. You can read how it works in the Città Fiera case study and compare approaches on indoor positioning without beacons or in our indoor navigation overview.

FAQ

When should you keep GPS instead of VPS?

Keep GPS for open outdoor areas, long distances and any place you have not mapped. It needs no venue hardware and no map of your own. Typical split: GPS from the highway to your parking lot, VPS from the entrance to the destination and between floors.

How accurate is a visual positioning system indoors?

A well-mapped VPS can relocalize a phone with centimeter-level accuracy and also estimate which way the camera is facing. Accuracy depends on the quality and freshness of the 3D map, the lighting and how much visual texture the camera can see.

Does a VPS need beacons or Wi-Fi in the building?

No. A camera-based VPS uses only the phone camera and a 3D map of the venue. You can still keep existing beacons or Wi-Fi for other uses, such as staff tools or connectivity.

What drives the cost of adding VPS to a venue?

The main factors are floor area, number of floors, venue type, how often the layout changes, whether mapping is included, and which channels you need: phones, website, kiosks. The number of sites matters too. A quote starts from these inputs.

Does VPS work in a parking garage?

It can, if the parking garage is mapped and has enough visual detail such as signs, pillars and markings. Very uniform or dark levels are harder, so test them during mapping.

If you are weighing VPS vs GPS for your venue, talk to our team about your floor area, number of floors and entrances.