“There are 50 apps in this category” can mean a healthy, fragmented field — or one giant and 49 ghosts. One number hides the part that decides whether you can win.
47 apps where the top 3 hold 71% of installs is a near-monopoly. 47 evenly-split apps is an opportunity. Same count, opposite verdict.
A market can be large and dying, or small and accelerating. Without momentum, you can’t tell if you’re early or late.
Install counts, ratings and review volume don’t show up in a category page — but they decide how hard it is to get noticed.
Not a TAM slide — the metrics that tell you if there’s room to land.
ScanGap crawls every public app in the niche so the app count is real and complete, not whatever a category page chooses to show.
It computes how installs and reviews cluster. A few apps holding most of the share means the door is mostly shut, however many apps exist.
New entrants and recent updates show whether the niche is still accelerating or quietly stalling — early vs. late, in one number.
Count, concentration and momentum together tell you what a market-size slide can’t: whether there’s actually room for one more app — yours.
Size my market free →Same scan, different question. Pick the job that fits where you are.