62
Quality Score
Solid
Z21 Updater
Medium confidence
✍️ bumetric analysis
“
Z21 Updater is an Android app from Roco | Fleischmann | Z21 in the Entertainment category, currently rated 5.0★ across 281 ratings. Initial signal reads as mixed reviews: supporters praise core features while critics cite stability and value gaps.
Quality Score is 62: Solid (established niche player). For a Entertainment app, that means established niche player. The full BU Investment Matrix below scores 8 dimensions including monetisation, growth, and operational risk.
Track changes month-over-month in the Performance section below: live snapshot history and revenue forecast included.
💰 Monthly revenue · now vs forecast
● Right now
$500
per month
→
12-mo forecast
$437 – $1575
per month
→
24-mo forecast
$405 – $3644
per month
INDIE tier
💡 Grow this revenue
Free AI audit of this app’s store listing
- Title & subtitle keyword fit
- Description hook & conversion structure
- Screenshots, ratings, reviews strategy
Typical impact: +2-5× organic installs
📊 Performance Tracking LIVE
Loading…
Rating
—
Reviews
—
Forecast Revenue / mo
—
Snapshots tracked
0
since first record
ONE-TIME · BUILD💰 Estimated build cost
$175K
↳ What it cost to build · not monthly revenue
Likely range $130K – $235K
$25K · MVP floor$100K · indie scale$500K+ · studio build
📈Slow ROI — current MRR is well below build cost
Synthetic estimate. Inputs: category complexity, file size, screen count, monetization layer, platform reach, age × team-size proxy. Calibrated against 2024-2026 indie-agency rate surveys. Full math + source list on /methodology.
Where the money goes
| 🧱MVP baseline (design + 1-store ship) | +$28K |
| 📱5 unique screens × $4.5K | +$22K |
| ⚙Entertainment complexity ×1.30 | +$15K |
| 🌐Cross-platform reach (iOS + Android) | +$36K |
| ⚙12.5y maintenance × ~1-person team | +$75K |
Total estimate$175K
👥 Estimated audience size
29K
Lifetime downloads (US-equivalent)
Monthly active
1.3K
Daily active
520
Synthetic estimate from ratings × category benchmarks. Calibrated against 2024-2026 mobile-attribution retention + DAU/MAU reports. Numbers are US-storefront-equivalent — true global audience can be 5-10× larger for international apps. Full math + source list on /methodology.
How we sized it
| 📲Entertainment engagement | ~150 installs / rating |
| 📅12.5y of rating accumulation | -30% |
| 🔁Entertainment D30 retention | 12% |
| 📍DAU / MAU stickiness | 0.40 |
DAU / MAU40% sticky
🛠 Estimated tech stack
🤖
Native Android (Kotlin)
High confidence · 80%
Also possible
Flutter
Heuristic guess from app bundle size, category, store description signals, and release-date stack era. Bumetric does not disassemble binaries — for binary-level certainty you would need an SDK intelligence tool or the manifest itself. Reasoning chain on the right. Full ruleset on /methodology.
Signals we read
| 🏷Category context | Entertainment |
| 📦Compact Android bundle | → Native Kotlin |
💀 Maintenance status
Likely abandoned
95%
Last shipped 2024-04-24 · 760 days ago
0 · Active50 · At risk100 · Abandoned
Heuristic risk score from time-since-last-update + ratings velocity proxy + Editor's Choice / curated featuring signals. Calibrated against 2024-2025 app-store ranking decay reports. Not a guarantee — a quiet app with a healthy codebase looks the same as an abandoned one until something breaks. Full math on /methodology.
Risk signals
| 📅2y+ since last update | Likely abandoned |
| 👥Small user base (281 ratings) + 12.5y old | +10% (solo-project pattern) |
| •13y old + 1y+ no update | +5% (API deprecation drift) |
VerdictLikely abandoned
🔬
How we forecast this revenue
LOW CONFIDENCEBaseline
$500/mo · ML-estimated from 234 triggers
Growth rate
+6.0% MoM · INDIE tier baseline (compound monthly)
6 months
$426 – $993
12 months
$437 – $1.6K
24 months
$405 – $3.6K
Compound growth at +6.0% MoM (tier baseline for INDIE). Range widens with horizon — typical noise band ±40% at 6mo.. Ranges widen with horizon — distant futures carry more uncertainty.
📊
BU Investment Matrix
Early-stage solo · 40/100INDIE TIERexpected for tierGrowth Velocity
5.0
Founder Strength
4.6
Product Quality
5.5
Revenue Strength
2.7
Monetization Maturity
1.0
Defensibility
3.5
Market Position
0.0
Operational Safety
10.0
- 💰 Revenue: Marginal — $200 - $1250/mo · INDIE tier · medium confidence, trajectory unclear.
- ⭐ Quality: 3.9★ across 196 reviews — below category median.
- 📍 Market: Not yet charting in any of the 9 monitored markets.
- 📈 Growth: Insufficient signal to assess trajectory.
- ⚠️ Risk: Low — no material risk signals detected.
🎯 For competitors: Mixed picture. Worth competing if you have a clear UX or pricing edge — otherwise crowded segment.
💵 For acquirers: Estimated asking range 18-32× monthly = $9K-$16K. Portfolio play ($822/mo combined) commands premium.
Composite of 8 dimensions computed deterministically from public signals — no LLM, every score traces back to a measurable input. Default weights shown; "compete" / "acquire" / "invest" lenses re-weight without re-fetching.
Range:
💰 Forecast Revenue / mo
MODELRevenue forecast computed from BU's 234 trigger model on each snapshot. Calibrated against ground-truth from 58 verified-revenue apps.
🔬Forecast Breakdown — Why This Estimate?Top 4 of 4 triggers
Our ML model uses 200+ signals from public data. These are the most influential for this app:
| Excellent rating (5.0★)METRIC | +$2,200 | |
| Mature app (12y old)METRIC | +$1,500 | |
| Ad-supported / freemiumMETRIC | +$600 | |
| Early-stage install base (281 ratings)METRIC | +$400 |
METRIC = structural app data · REVIEW = mined from user reviews · ✓ VERIFIED = Stripe-verified anchor (TrustMRR)
📈 Reviews Growth
LIVECumulative review count from first BU snapshot. Each point = a tracked update.
⭐ Rating Trend
LIVEAverage rating evolution. Updates with each new review batch.
App Specs
🔐 Own this app? Claim & verify MRR →🔖 v2.1.1🔄 updated 2y ago📂 Entertainment💰 Free🚀 Launched 2013 (12y old)
📝 About this app
This app allows you to conveniently keep your Z21, z21, z21start and smartRail always up to date.
The connected device is automatically recognized by the app. New updates are directly queried from the server when connected to the Internet thus the update process is very simple and functional.
The connected device is automatically recognized by the app. New updates are directly queried from the server when connected to the Internet thus the update process is very simple and functional.
🔔
Track this app’s revenue
FREEGet an email when revenue moves by your threshold. No spam, unsubscribe in one click.
Profile & Insights
Everything we know — and don't — about this app and its company.
Identification
- App name
- Z21 Updater
- Developer
- Roco | Fleischmann | Z21
- Bundle ID
- com.z21.z21fwupdate
- App Store URL
- Open in App Store
- Category
- Entertainment
- Content rating
- Not found
- Languages
- Not found
Company
- Website
- www.z21.eu
- Tagline
- Not found
- Description
- Not found
- Founded
- Not found
- HQ / Address
- Not found
- Employees
- Not found
- Logo
- Not found
Revenue
- Verified revenue / mo
- Not found
- AI revenue estimate / mo
- Not found
- AI annual estimate
- Not found
- ML model estimate / mo
- $299/mo
- Top-grossing rank
- Not found
- All-time revenue
- Not found
- Pricing
- Not found
Founder
Founder data not yet collected for this app.
Funding
Funding data not yet collected for this app.
Press & Links
Press & Links data not yet collected for this app.
Contacts & Socials
Contacts & Socials data not yet collected for this app.
📈Ratings growth281 ratings+40% lifetimeShow 3-year history estimate ▾
Tracked (1 weeks) Pre-tracking estimate (36 weeks) · model-based, ±5% noise · anchored to release date and current value
Profile is built from iTunes Lookup + developer site scrape + ML revenue model. Empty fields show "Not found" — additional sources (Crunchbase, X, IndieHackers, Acquire.com) coming.
More by Roco | Fleischmann | Z21
View all →📦 Portfolio summaryINDIE studio
3apps·$986/mocombined
Lead-app heavy — top app contributes 56%
Similar apps in Entertainment
Full revenue analysis
Read the article-style breakdown for Z21 Updater: category rank, percentile, growth signal, comparable apps, and how the forecast is calibrated against verified-MRR anchors in this niche.
About this analysis
Why medium confidence: 281 ratings · no founder-verified revenue (model estimate only).
❓ Frequently Asked Questions
9 answers · auto-generated from this app's public dataHow much does Z21 Updater make per month?▴
Based on our ML-calibrated revenue forecast, Z21 Updater earns approximately $298/mo. This is a US-storefront-equivalent estimate; global revenue can be several times larger for internationally-distributed apps. See the methodology page for the full formula and confidence bands.
Is Z21 Updater profitable?▴
With estimated build cost $175K and monthly revenue $298, Z21 Updater looks well below break-even — current monthly revenue is much smaller than the estimated build cost. Profitability also depends on paid-acquisition spend and refund rate which the public model doesn't see.
How many users does Z21 Updater have?▴
Estimated audience: ~29K lifetime downloads, ~1K monthly active users, and ~520 daily active users. Derived from ratings count × category installs-per-rating × age decay. US-storefront-equivalent — global audience can be 5-10× larger for internationally-distributed apps.
What apps are like Z21 Updater?▴
Browse the full Entertainment category catalog to find similar apps with revenue, build cost, audience and tech stack data. Each /p/{slug} page also shows a Compare side-by-side widget with three peer apps from the same niche.
What is Z21 Updater built with?▴
Our heuristic places Z21 Updater on the Native Android (Kotlin) stack (High confidence, 80%). Signals: app bundle size, category context, store-description markers, release-date era. We don't disassemble binaries. Alternative possibilities: Flutter.
Is Z21 Updater still actively maintained?▴
Maintenance status: Likely abandoned (95% abandonment risk). Last shipped version was 2+ years ago. The risk score combines time-since-last-update with Editor's Choice / curated featuring + user-base maturity adjustments.
When was Z21 Updater last updated?▴
Z21 Updater last shipped a new version on 2024-04-24 — more than 2 year(s) ago. This is the date Apple / Google last accepted a new build, not a content-only push.
Who makes Z21 Updater?▴
Z21 Updater is published by Roco | Fleischmann | Z21 on the Google Play Store. See the full publisher portfolio (other apps by the same developer) via the More by developer block on the product page above.
What is Z21 Updater's BU Score?▴
Z21 Updater has a BU Score of 62/100 (Solid). The score combines App Store rating, ratings count, monetization model and revenue signals calibrated against founder-verified MRR anchors. See the BU Score formula.