Appworthy
Pay to progress
2 independent sources agreePay to progress: raised by 8 distinct reviewers (about 1 in 50 reviews we read)
Definition
Advancement or competition is gated behind spending money rather than playing.
Google Play rating4.5★4.5K ratings
PriceFreeIn-app purchases
Age9+Store age rating
CategoryGames
DeveloperEfun Game Ltd.
What we found
Full reportSerious warnings 1 confirmed warning, and users report 1 more thing. Checked: 400 reviews, the Android app’s code, the store listing and the privacy label.
Money
- Free to download · in-app purchases. Google Play doesn’t publish per-purchase prices.
- Pay to progressConfirmed
- If you subscribe through the store, cancel in Google Play → Payments & subscriptions → Subscriptions. Deleting the app doesn’t cancel a subscription.
Pressure and ad claims
Positives
From our automated analysis, 31 Oct 2026. Every label links to its evidence in the full report below.
This analysis describes version 1.0.15 of the app (the version number recorded inside the package we inspected), analyzed 2026-10-31 .
The store currently lists version 1.0.15, updated 2026-07-30.
Preview
Store screenshots supplied by the developer.
About this app
[Game Features]
Even a rookie skull can become the Skull King! In Skull Up, you will rise from the bottom to the throne: collect over 60 Skellies to form your unique teams, enjoy idle management with abundant rewards, and unlock multiple adventures. Come and unleash the power of the undead and evolve from a nobody into the Skull King!
[Endless Fun, Underworld Adventures]
A rookie skull uncovered hidden treasures! In Skull Up, you can amass massive resources through management gameplay, or defeat mighty enemies with smart strategies. Join a guild and fight alongside your bone buddies! More content await—nonstop excitement guaranteed!
[Diverse Skellies, Boundless Power]
Gather various Skellies during your path to becoming the King! During this adventure, you will encounter over 60 unique Skellies with distinct looks and abilities.…
From the developer’s store description.
For developers and the curious
The full report
The evidence, sources, measurements and versions behind every label above.
Findings and evidence
Things to watch for 1
Findings that met the published evidence standard.
Open evidence
Positives 2
Specific evidence of a useful property, within the stated scope.
Developer says data deletion can be requested
MeasuredThe developer's store data-safety disclosure states that data deletion can be requested; we have not seen a deletion control in the app's own text
Definition
The developer's data-safety disclosure on the store states that users can request deletion of their data, or the app's own text offers a way to delete the account. This restates what the developer declares; it is not a test of whether deletion works. Apple publishes no equivalent disclosure, so on an Apple-only listing only the app's own text can support it.
No advertising SDKs
MeasuredNo advertising or mediation SDK among the 7 SDKs detected in the package
Definition
No advertising or mediation SDK of any kind was found in the package.
How we know
Package artefact
sha256:0635ebe4186a0e2c9bc906ebf1abe373043e884af64dd7c7a4b3a1df21720e65One source only — shown, not confirmed 3
Open observations that have not cleared the evidence bar.
Reports that the ads misrepresent the app
One source onlyMisleading advertising: raised by 20 distinct reviewers (about 1 in 20 reviews we read)
This observation has not cleared the required evidence standard.
Definition
Reviewers repeatedly report that the app is not what its advertising showed. We never see the ad creative itself, so nothing we collect can corroborate or refute this — it is published as an attributed user report: what reviewers say, and how many of them said it.
How we know
Usable without an account
One source onlyThe app's own text says: "Akun tamu"
This observation has not cleared the required evidence standard.
Definition
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.
How we know
Package artefact
sha256:0635ebe4186a0e2c9bc906ebf1abe373043e884af64dd7c7a4b3a1df21720e65Works offline
One source onlyThe app's own text says: "Entre novamente no jogo para me ver depois de se esconder"
This observation has not cleared the required evidence standard.
Definition
The app's own copy describes working without a connection — offline mode, downloading for offline use, or content saved for later. Shown because readers filter on it; it is a feature, not a fairness property, and never counts for or against an app.
How we know
Package artefact
sha256:0635ebe4186a0e2c9bc906ebf1abe373043e884af64dd7c7a4b3a1df21720e65What reviewers report
400 reviews read for this analysis. Each observation keeps the sample and store it was based on.
Pay to progress
Published findingI really, really wanted to love this game, as I love skulls. To summarize, there's 3 currencies you have to use to level up your skulls. You will be bottlenecked. Second, it's so P2W, it makes Slime Castle look F2P friendly. You need at…
This game is great and addicting but ultimately dont waste your time, its comepletely pay to win.. ppl that spend $1000's are on top and will be forever. So if youre rich then this game is great.
it is nothing like the ads , absolutely nothing , it is kind of fun , very much pay to win ,
Reports that the ads misrepresent the app
Shown, not confirmedit is nothing like the ads , absolutely nothing , it is kind of fun , very much pay to win ,
this is nothing like the advertisements. it's a shameless cash grab, and the tutorial drags on forever. classic mobile game, the only thing it has going for it is that it doesn't have an energy system.
This game is not what was advertised... 😑
A sampled review illustrates one person’s experience. It does not establish a finding on its own.
Measurements
“Not assessed” means we could not measure it. It is never a zero and never a pass.
From store data and reviews
Developer replies to reviews
Replies to fewer than 1 review in 20
Price in the store description
The store description doesn’t list prices (most don’t)
Cancelling, in the store description
The store description doesn’t say how to cancel (most don’t)
Themes reported by reviewers
2 themes 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 app package we scanned
Android package 1.0.15, scanned 30 Oct 2026. These describe that package, not the current store version.
Sensitive permissions
1–2 requested
Counted against a fixed list of eighteen sensitive Android permissions: sixteen runtime permissions, among them location, camera, microphone, contacts and SMS, and two the user must switch on in system settings, drawing over other apps and usage access. Requesting one is not itself a finding.
Analytics or tracking SDKs in the scanned package
1–2 found
Advertising SDKs in the scanned package
None found
Counted as distinct SDKs in the package we scanned. One mediation bundle can contribute several, so this is not a count of advertisers.
How we know
Supporting measurements: not a complete list of possible harms or positives. Measurement vocabulary 1.4 · how these are measured
Versions and dates analysed
This analysis describes version 1.0.15 of the app (the version number recorded inside the package we inspected), analyzed 2026-10-31 .
The store currently lists version 1.0.15, updated 2026-07-30.
Store update history
Each store’s release notes, as the developer wrote them. They are the developer’s words, not ours.
Google Play
Version 1.0.15 · 2026-07-30
No release notes were provided for this version.
Assessment record
- Status
- Automated analysis
- App identifier
skull-up-google-com-efun-euklqb- Assessment date
- 31 Oct 2026
- Sources used
- 6 independent signals: user reviews, SDKs in the app package, the app's own on-screen text, the app manifest, the store listing and the store privacy disclosure
- Reviews read
- 400
- Package examined
- Android · 1.0.15 · scanned 30 Oct 2026
- Human inspection
- Not completed
Assessed 2026-10-31 from 400 user reviews, the app's package, the store listing and its privacy label.
How we know
- Measurement vocabulary
- 1.4
How this page was produced
Analyzed 2026-10-31 Version analyzed: 1.0.156 independent signals400 reviews scannedConfidence: HighNot human-reviewedVocabulary v1.14Methodology v1.3
Signals run: user reviews, SDKs in the app package, the app's own on-screen text, the app manifest, the store listing and the store privacy disclosure.
Store facts
What the stores publish. Store ratings are the stores’ numbers, not Appworthy’s, and are never averaged across stores.
Google Play
- Store rating
- 4.52 ★ · 4,464 ratings
- Version
- 1.0.15
- Updated
- 30 Jul 2026
- Price
- Free · In-app purchases
- Age rating
- 9+
- Size
- Not supplied
- Developer
- Efun Game Ltd.
- Category
- Games
- Listing price
- Free · In-app purchases
Purchases the store lists
What this app sells
Google Play doesn’t publish per-purchase prices.
Method and limits
How the automated analysis works
This assessment is produced automatically. Six independent signals are read — user reviews, SDKs in the app package, the app's own on-screen text, the app manifest, the store listing and the store privacy disclosure — and each candidate finding is filed under the sources that support it.
No charge stands on one kind of evidence — with one published exception. A finding is either a measured fact that anyone can reproduce (an ad SDK is in the package; every recurring plan the store lists is named as weekly, the term read from the purchase names, with a list cut off at the store’s 10-item maximum not assessed; the privacy label omits a tracker we can see), or it is an interpretation — and an interpretation needs independent sources to agree before it reaches the catch list. The exception is a harm only users can see: a charge may publish from reviews alone, as “Reported by N users”, once enough reviewers raise it to clear that charge’s own published bar. That agreement rule is what replaced the human reviewer, not a model’s confidence.
There is no overall score, on purpose. A 0–99 number was published here until 2026-09-15. It was withdrawn because it discriminated too weakly to be the instrument — 44.7% of every pair of apps tied — and because a single number is a verdict where a count is an observation. What publishes instead is a row of measurements, each of which says what was counted and, where we could not look, says that instead.
Findings under One source only are real reports we do not stand behind as findings. They are shown because withholding them entirely would hide a genuine complaint, and labelled because publishing them as charges would be an accusation off a single source.
Limits of this report
- A package scan is static. It identifies code and text in one Android build. It does not measure a live ad session, test a deletion request, or count the steps needed to cancel.
- Reviews keep their sample. A review-only charge shows distinct reviewers, the share and the sample size, and is published only once it clears that label’s published threshold. Calibration labels are machine-drafted and not yet confirmed by a person.
- Not assessed is a state. It is never a zero and never a pass.
- A missing label is not a clean bill of health. It means the evidence did not support one, not that the app is problem-free.
Not yet human-reviewed. A hands-on test can confirm or contradict a finding and adds its own measurements; it does not change a measurement row. Hands-on inspections are not yet open.
Request a correction
Write to [email protected], or use the form. Name the finding, the app version and the evidence that needs correcting. Factual corrections are free and never depend on buying anything.