“Accurate db meter! — Surprisingly accurate for a free RTA app. Next to regular db meter pretty much the same. This cannot be said for every other free RTA app I have tried since I got my first iPhone in 2012. Perfect for monitoring bands…”
Independent automated assessment · 3 signal sources · 303 reviews scanned · analyzed 2026-10-07.
4.7 ★162,540 ratings
—Downloads
4+Age rating
94 MBApp size
FreeIn-app purchases
About this app
"Decibel X" is one of very few noise meter apps on the market that has highly reliable, pre-calibrated measurements and supports dBA, dBC. It turns your iOS device into a professional sound level meter, precisely measures the sound pressure level (SPL) all around you. This extremely useful and beautiful tool will not only be a great tool for many uses but also bring you a lot of fun. Have you wondered how quiet is your room or how loud is a rock concert or sport event? "Decibel X" will help you answer all of those.
WHAT MAKE IT GREAT AND STAND OUT FROM OTHER APPS:
- Trusted accuracy: the app is tested and pre calibrated for all Apple devices.…
Preview
Real screenshots from the store listing.
Independent evidence report
Evidence and review signals
This is where the page changes from an app-store listing into an evidence report: findings, important reviews, pricing and a dated history.
Which version this describes
When we ran this analysis, and what the store lists now.
This analysis describes version 9.9.7 of the app, analyzed 2026-10-07 . The app may have changed since.
The store currently lists version 9.9.7, updated 2026-09-15.
What we measured
Each line is a measurement published as a measurement, never a verdict.
Each line is a measurement, published as a measurement. Where we have not looked, the line says so rather than reading as a zero.
Developer replies to reviews
Replies to fewer than 1 review in 20
Price in the store description
States no price and billing period
Cancelling, in the store description
Does not say how to cancel
Themes reported by reviewers
1 theme reported
Counted from the reviews we have read for this app. "No theme reported" means no theme reached our reporting threshold — it is not a finding that nothing is wrong with this app, and we do not say it is.
Five-star share of ratings
65–79% five-star
Arithmetic on the stores' own published rating counts. It says nothing about why the ratings fall where they do.
In the package we scanned
No package has been scanned for this app, so nothing is published about what it ships. That is an absence of evidence about the app, not a finding about it.
Graded bands · predicate set 1.4 · how these are measured
What the analysis found
App-specific findings, grouped by what each one rests on. How they are graded lives on its own page.
One source only — shown, not confirmed 2
A single kind of evidence. We publish these because withholding them would be the bigger distortion, and we do not treat any of them as a finding we stand behind.
Reported by users: Upgrade prompts use guilt-trip wording
Declining an upgrade is written as a loss ('No thanks, I don't want to improve'), or users report being repeatedly pushed to subscribe during normal use.
What we saw: Constant upsell pressure: raised by 6 distinct reviewers (2.0% of 303 reviews scanned)
From the store listing: Usable without an account
The app's own screens offer a way past sign-up — guest access, skipping, or browsing before registering — rather than gating the product behind an account. The store's privacy disclosure is checked alongside it: that disclosure is self-reported, so it corroborates this credit rather than establishing it.
What we saw: The store privacy disclosure (2 entries) links no contact details or identifiers to the user — consistent with an app that does not require an account. Self-reported by the developer.
Highlighted reviews
Representative public review excerpts shown as user reports, not Appworthy audit evidence.
“Free version unusable — The free version of this app is not useable as there are constant pop ups again and again and again prompting you to upgrade to the paid version. If developers don’t want to offer a free version of their app…”
“Tired of the upsell — Everytime you open the app you're prompted to upgrade to premium. Every. Single. Time. That got old real fast -- 3 days, actually. So I deleted it.”
Assessment & version history
App changes and Appworthy events in one timeline.
Store listing updated to version 9.9.7.
What this app sells
Useful store-disclosed pricing, kept below the app listing.
Business modelFree
Prices and terms as disclosed by the store listing.