Spark + AI: Persönliche E-Mail
76
Quality Score
Strong
✍️ Bumetric analysis
“
Spark + AI: Persönliche E-Mail is an iOS app from Readdle Technologies Limited in the Productivity category, currently rated 4.6★ across 81,532 ratings. Initial signal reads as mixed reviews: supporters praise core features while critics cite stability and value gaps.
Quality Score is 76: Strong (healthy traction). For a Productivity app, that means healthy traction. 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
$1.5M
per month
→
12-mo forecast
$1.6M – $2.4M
per month
→
24-mo forecast
$1.9M – $3.5M
per month
BIG 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
319 snapshots on record
Rating
4.6
Reviews
81,532 reviews
Forecast Revenue / mo
$1.5M
Snapshots tracked
319
since Nov 2024
ONE-TIME · BUILD
💰 Estimated build cost
$170K
↳ What it cost to build · not monthly revenue
Likely range $130K – $230K
$25K · MVP floor
$100K · indie scale
$500K+ · studio build
📈
Pays back in under a month at current MRR
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 |
| 📦 Asset bundle (351 MB) | +$40K |
| ⚙ Productivity complexity ×1.10 | +$9K |
| ⚙ 11.3y maintenance × ~1-person team | +$67K |
Total estimate
$170K
ONE-TIME · EXIT VALUE
💵 Estimated acquisition value
$31.5M
↳ What it would sell for · not monthly revenue
Marketplace range $23.5M – $41.0M · 21× MRR multiple
💸
~185× return on build cost
Synthetic estimate. Multiple band derived from ad-supported + age, rating quality, category demand, and user-base maturity. Calibrated against 2024-2026 indie-app-marketplace closed-deal medians. Full math + comparable deal list on /methodology.
How the multiple was built
| 📺 Ad-supported base | 15× MRR |
| 📅 11.3y proven track record | +20% |
| ⭐ ★ rating ≥ 4.4 (solid) | +8% |
| 🏷 Productivity category multiple | +8% |
Final multiple
21× MRR
👥 Estimated audience size
4.2M
Lifetime downloads (US-equivalent)
Monthly active
560K
Daily active
250K
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
| 📲 Productivity engagement | ~75 installs / rating |
| 📅 11.3y of rating accumulation | -30% |
| 🔁 Productivity D30 retention | 30% |
| 📍 DAU / MAU stickiness | 0.45 |
DAU / MAU
45% sticky
🛠 Estimated tech stack
🍎
Native iOS (Swift / UIKit)
Medium confidence · 55%
Also possible
React Native
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
| 📦 App bundle size | 351 MB |
| 🏷 Category context | Productivity |
| 📦 Large iOS bundle | → Native Swift / UIKit (pre-2020 era) + assets |
💀 Maintenance status
Active
5%
Last shipped 2026-08-27 · 30 days ago
0 · Active
50 · At risk
100 · 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
| 📅 30 days since last update | Active development |
Verdict
Active
🔬
How we forecast this revenue
MEDIUM CONFIDENCEBaseline
$1.5M/mo · ML-estimated from 234 triggers
Growth rate
+2.5% MoM · BIG tier baseline (compound monthly)
6 months
$1.5M – $2.0M
12 months
$1.6M – $2.4M
24 months
$1.9M – $3.5M
Compound growth at +2.5% MoM (tier baseline for BIG). Range widens with horizon — typical noise band ±15% at 6mo.. Ranges widen with horizon — distant futures carry more uncertainty.
📊
BU Investment Matrix
Mixed signals · 61/100BIG TIERcompetitive but cautiousGrowth Velocity
5.0
Founder Strength
7.6
Product Quality
9.3
Revenue Strength
6.2
Monetization Maturity
1.0
Defensibility
7.5
Market Position
2.0
Operational Safety
10.0
- 💰 Revenue: Healthy — $600K - $3300K/mo · BIG tier · medium-low confidence, trajectory unclear.
- ⭐ Quality: 4.63★ across 81,532 reviews — exceptional (top 1% in category).
- 📍 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 = $27.0M-$48.0M.
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 15 of 15 triggers
Our ML model uses 200+ signals from public data. These are the most influential for this app:
| Mid install base (81,532 ratings)METRIC | +$5,500 | |
| Paid app ($0.00)METRIC | +$2,800 | |
| Excellent rating (4.6★)METRIC | +$2,200 | |
| worth every pennyREVIEW | +$2,000 | |
| bugsREVIEW | −$1,800 | |
| 5 starREVIEW | +$1,800 | |
| cancelledREVIEW | −$1,500 | |
| excellent appREVIEW | +$1,500 | |
| Mature app (11y old)METRIC | +$1,500 | |
| Multilingual (10 languages)METRIC | +$1,500 | |
| highly recommendREVIEW | +$1,400 | |
| slowREVIEW | −$1,200 | |
| too expensiveREVIEW | −$1,000 | |
| support teamREVIEW | +$900 | |
| priceyREVIEW | −$800 |
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.
🆕 What's New · v3.19.26
In this release, we've addressed the following issues:
- Fixed an issue where deleted or hidden folders could still appear for Microsoft accounts.
- Fixed an issue where the Read Statuses information link was missing.… Full release notes →
- Fixed an issue where deleted or hidden folders could still appear for Microsoft accounts.
- Fixed an issue where the Read Statuses information link was missing.… Full release notes →
Profile & Insights
Everything we know — and don't — about this app and its company.
Identification
- App name
- Spark + AI: Persönliche E-Mail
- Developer
- Readdle Technologies Limited
- Bundle ID
- com.readdle.smartemail
- App Store URL
- Open in App Store
- Category
- Productivity
- Content rating
- 4+
- Languages
- EN, FR, DE, IT, JA, PT, RU, ZH, ES, UK
Company
- Website
- Not found
- Tagline
- Today
- Description
- Find apps and games for iPhone, iPad, Mac, and more on the App Store.
- Founded
- Not found
- HQ / Address
- Not found
- Employees
- Not found
- Logo
- Available
Revenue
- Reported revenue signal / mo
- Not found
- AI revenue estimate / mo
- Not found
- AI annual estimate
- Not found
- Model estimate / mo
- $1.5M/mo
- Top-grossing rank
- 🇩🇪#59 /100 🇯🇵#85 /100
- 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 growth82,347 ratings+17200% lifetimeShow 3-year history estimate ▾
Tracked (60 weeks) Pre-tracking estimate (0 weeks) · model-based, ±5% noise · anchored to release date and current value
🌍Top Countries — Grossing Rank2 countries
🇩🇪DE#59 /100
🇯🇵JP#85 /100
📊Category Rank Trajectory#59 now · best #59 · worst #59
Lower line = better rank · Estimate from ratings growth model · Lower position on chart = worse rank · Higher = top of chart
🚀Update Frequency · Releases per Quarter9 releases tracked
🚀Version Release Timeline8 releases tracked
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.
📝 About this app
Manage priorities, not emails.
Spark brings every account into one inbox and automatically surfaces what matters most — so nothing slips through the cracks. Loved by millions and named "Best of the App Store" by Apple.
"It's a combination of polish, simplicity, and depth." — FastCompany
"You can create an email experience that works for you." — TechCrunch
EVERY ACCOUNT, EVERY EMAIL, IN ONE PLACE
Connect Gmail, Outlook, iCloud, Yahoo, AOL, Hotmail, GMX, and any IMAP account in a single unified inbox.
STAY ORGANIZED WITH SMART INBOX
Important emails from real people rise to the top.… View full description on the official store →
Spark brings every account into one inbox and automatically surfaces what matters most — so nothing slips through the cracks. Loved by millions and named "Best of the App Store" by Apple.
"It's a combination of polish, simplicity, and depth." — FastCompany
"You can create an email experience that works for you." — TechCrunch
EVERY ACCOUNT, EVERY EMAIL, IN ONE PLACE
Connect Gmail, Outlook, iCloud, Yahoo, AOL, Hotmail, GMX, and any IMAP account in a single unified inbox.
STAY ORGANIZED WITH SMART INBOX
Important emails from real people rise to the top.… View full description on the official store →
App Specs
🔐 Own this app? Claim & verify MRR →💾 351 MB🔞 4+📱 iOS 16.4+🔖 v3.19.26🔄 updated 1mo ago🌐 EN, FR, DE, IT, JA +5📂 Productivity💰 Paid🚀 Launched 2015 (11y old)
📅
What Worked™ · Development Pipeline
25 EVENTS TRACKEDDetected changes in this app over its tracked lifetime — each event links cause (what changed) to effect (what moved). Sorted newest first.See full history →Version history →
2026-09
📦
Bundle ↓ 624MB → 368MB — likely major code refresh
2026-08
🔧
Shipped update — v3.19.23 → v3.19.26
→ 30 days after: reviews +160 high confidence
2026-07
🔧
Shipped update — v3.19.22 → v3.19.23
→ 30 days after: reviews +292 medium · co-occurring
2026-07
🔧
Shipped update — v3.19.21 → v3.19.22
→ 30 days after: reviews +335 medium · co-occurring
2026-07
🔧
Shipped update — v3.19.19 → v3.19.21
→ 30 days after: revenue −$4.6K/mo · reviews +206 medium · co-occurring
2026-07
🔧
Shipped update — v3.19.18 → v3.19.19
→ 30 days after: revenue −$4.6K/mo · reviews +252 medium · co-occurring
2026-06
🔧
Shipped update — v3.19.17 → v3.19.18
→ 30 days after: revenue −$4.6K/mo · reviews +263 high confidence
2026-06
🔧
Shipped update — v3.19.15 → v3.19.17
→ 30 days after: reviews +285 high confidence
2026-05
🔧
Shipped update — v3.19.14 → v3.19.15
→ 30 days after: reviews +311 high confidence
2026-05
📈
Crossed 1,000 ratings — social-proof flywheel kicking in
→ 30 days after: reviews +259 high confidence
2026-05
⭐
Rating ↑ 3.10 → 4.63 (improved 1.53★)
→ 30 days after: reviews +259 high confidence
2026-03
📈
Crossed 500 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$2.3M/mo · rating +1.40★ · reviews +80,475 high confidence
2026-03
⭐
Rating ↑ 3.10 → 4.50 (improved 1.40★)
→ 30 days after: revenue +$2.3M/mo · rating +1.40★ · reviews +80,475 high confidence
2025-01
📈
Crossed 100 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$722/mo · rating +0.16★ · reviews +26 medium · co-occurring
2025-01
📈
Crossed 100 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$1.8K/mo · rating +0.20★ · reviews +68 low · multiple changes
2024-12
📈
Crossed 50 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$1.1K/mo · reviews +42 high confidence
2024-12
📈
Crossed 50 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$2.1K/mo · reviews +80 high confidence
2024-11
🚀
First tracked snapshot — initial data captured
→ 30 days after: revenue +$975/mo · reviews +38 high confidence
2024-11
📈
Crossed 10 ratings — social-proof flywheel kicking in
→ 30 days after: revenue +$975/mo · reviews +38 low · multiple changes
2024-11
⭐
Rating ↑ 2.57 → 2.88 (improved 0.31★)
🌍
Multi-Country Performance
Available in 9 of 9 monitored markets| Market | Rating | Reviews | Current version |
|---|---|---|---|
| 🇦🇺 AU | 4.59374★ | 7,313 | 4.59374★ this version |
| 🇧🇷 BR | 4.76809★ | 9,767 | 4.76809★ this version |
| 🇨🇦 CA | 4.57627★ | 11,132 | 4.57627★ this version |
| 🇩🇪 DE | 4.47316★ | 28,753 | 4.47316★ this version |
| 🇫🇷 FR | 4.57352★ | 14,111 | 4.57352★ this version |
| 🇬🇧 GB | 4.56104★ | 13,737 | 4.56104★ this version |
| 🇮🇳 IN | 4.69322★ | 5,887 | 4.69322★ this version |
| 🇯🇵 JP | 4.4078★ | 36,059 | 4.4078★ this version |
| 🇺🇸 US | 4.62435★ | 82,468 | 4.62435★ this version |
🔔
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📝 Description
95
BU Score · Transcendent
Full revenue analysis
Read the article-style breakdown for Spark + AI: Persönliche E-Mail: category rank, percentile, growth signal, comparable apps, and how the forecast is calibrated against verified-MRR anchors in this niche.
More by Readdle Technologies Limited
View all →📦 Portfolio summaryBIG studio
6apps·$8.9M/mocombined
✓ Diversified — top app contributes 17%; risk spread across portfolio
About this analysis
Why high confidence: 81,532 ratings · no founder-verified revenue (model estimate only).
❓ Frequently Asked Questions
10 answers · auto-generated from this app's public dataHow much does Spark + AI make per month?▴
Based on our ML-calibrated revenue forecast, Spark + AI earns approximately $1.5M/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 Spark + AI profitable?▴
With estimated build cost $170K and monthly revenue $1.5M, Spark + AI looks highly profitable — pays back its build investment in under a month at the current run-rate. Profitability also depends on paid-acquisition spend and refund rate which the public model doesn't see.
How many users does Spark + AI have?▴
Estimated audience: ~4.2M lifetime downloads, ~560K monthly active users, and ~250K 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 Spark + AI?▴
Browse the full Productivity 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 Spark + AI built with?▴
Our heuristic places Spark + AI on the Native iOS (Swift / UIKit) stack (Medium confidence, 55%). Signals: app bundle size, category context, store-description markers, release-date era. We don't disassemble binaries. Alternative possibilities: React Native, Flutter.
Is Spark + AI still actively maintained?▴
Maintenance status: Active (5% abandonment risk). Last shipped version was 1 months ago. The risk score combines time-since-last-update with Editor's Choice / curated featuring + user-base maturity adjustments.
How much would Spark + AI sell for?▴
Estimated acquisition value: $31.5M (marketplace range $23.5M – $41.0M). Calculated as 21× monthly revenue using the standard multiple for the detected monetization model + adjustments for age, rating quality and category demand. Calibrated against 2024-2026 Flippa / Acquire.com / MicroAcquire closed-deal medians.
When was Spark + AI last updated?▴
Spark + AI last shipped a new version on 2026-08-27 — 1 months ago. This is the date Apple / Google last accepted a new build, not a content-only push.
Who makes Spark + AI?▴
Spark + AI is published by Readdle Technologies Limited on the Apple App 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 Spark + AI's BU Score?▴
Spark + AI has a BU Score of 76/100 (Strong). The score combines App Store rating, ratings count, monetization model and revenue signals calibrated against founder-verified MRR anchors. See the BU Score formula.