Common map problems — and how I fix them
Almost every app that shows a map or a location runs into the same handful of problems. Here are seven of them — shown live, in plain language, each with the fix and what it means for your product and your customers. Flip the toggle on any card to watch the broken version become the fixed one.
01Shaky GPS makes distances and routes wrong
A phone's GPS is never perfectly accurate — it jumps around by a few metres every second. Shown as-is, a route looks messy and its distance comes out far longer than the real one.
Actual walk
2.62 km
App reports
4.75 km
Overstated by
+82%
GPS jumps counted as real travel
The app counts every tiny GPS jump as real movement, so a 2.6 km walk is reported as 4.7 km. Anything priced or reported by distance — delivery fees, mileage, pay-per-km, fitness stats — is overcharged or wrong, and people quickly stop trusting the numbers.
Business impact: Accurate distances mean correct billing, fewer refunds and complaints, and data your customers actually trust.
02One swapped coordinate puts the pin in the wrong country
Maps expect the two numbers of a location in a specific order. Flip them by mistake and the point silently jumps thousands of kilometres — with no error message to warn you.
Entered as
[lat, lng]
how people say it
Map expects
[lng, lat]
the map's order
Wrong by
2766 km
from the real Kyiv
With the two numbers swapped, Kyiv lands in a Saudi desert 2,766 km away — and nothing flags it. In a live product that means parcels sent to the wrong address, a 'store near you' that's across an ocean, and drivers dispatched to the wrong place.
Business impact: Locations land where they should — correct deliveries, credible search results, and none of the costly mistakes a misplaced pin causes.
03Trips across the Pacific drawn the wrong way
Near the line where the map wraps around (the far edge of the Pacific), a short trip can be drawn as a line streaking straight across the entire world.
Actual trip
8271 km
the real distance flown
Drawn line covers
~98° lng
almost the whole globe
A quick Tokyo→San Francisco hop is drawn streaking across the whole map, and any distance taken from it is wildly wrong. For airlines, shipping and global logistics that means nonsense routes and mis-priced trips.
Business impact: Correct international routes mean accurate delivery times and pricing for global logistics — no trips that look ten times longer than they are.
04The quick way to measure distance overcharges away from the equator
A simple 'straight-line' distance looks fine near the equator, but the further north or south you go, the more it overstates the real distance. Drag the slider to see the error grow.
Quick method
891 km
simple, but wrong up north
Correct method
445 km
accounts for the Earth's curve
Overcharged by
+100%
grows toward the poles
The quick method assumes the world is flat. Near the equator that's fine, but at the latitude of Kyiv, London or Toronto it can read almost twice the real distance — quietly inflating every distance-based fee, delivery estimate and report in those markets.
Business impact: Fair distances worldwide mean correct fees and estimates in every region — no hidden overcharging that erodes trust and invites disputes.
05Heavy routes slow the app — trim them without losing the shape
A recorded route stores far more points than the screen actually needs. All that extra data makes maps slow to load and jerky to use, especially on phones.
Original
1200
points
Trimmed
614
points
Data removed
−49%
same shape, far less data
Removing redundant points keeps the exact same shape with a fraction of the data — often 80–95% smaller. Maps load faster, use less mobile data, and feel smooth, especially on slower connections and cheaper phones.
Business impact: Faster maps and less data mean a better experience, lower bandwidth and hosting costs, and an app that works well even on weak connections.
06Thousands of pins freeze the map — group them
Putting every location on the map as its own pin means thousands of markers on screen at once — the map stutters and overlapping pins become an unreadable mess.
Locations
4,000
in this dataset
Shapes on screen
4,000
one per pin — slow & cluttered
With 4,000 individual pins the map lags and the pins pile on top of each other, so people can't tell what's where. Slow, cluttered maps make users give up and leave.
Business impact: Smooth, readable maps at any scale keep users engaged, work on cheaper devices, and let you show far more data without slowing down.
07Share the exact map view with a link
Zoom to a spot on this map, then reload the page — most maps forget where you were, so that view can't be bookmarked or sent to a colleague. This one remembers.
?v=15.0000,50.0000,3.40
Saving the map position inside the web address means the exact view comes back on reload and can be shared or bookmarked. Try it: drag and zoom, copy the link, open it in a new tab — the same view returns. Great for support ('here's the exact spot'), teamwork, and links in emails or reports.
Business impact: Shareable map links make support, collaboration and marketing easier — everyone lands on exactly the right view instead of describing it in words.
Each demo runs entirely in your browser — no servers, no data collected. The underlying calculations are covered by automated tests.