63
BU Score
Solid
RPN 28x Calc
✍️ bumetric analysis
“
RPN 28x Calc is an iOS app from tredje design in the Productivity category, currently rated 5.0★ across 33 ratings. Initial signal reads as largely positive sentiment, users highlighting consistency and feature depth.
Our BU Score puts it at 63: Solid (established niche player). For a Productivity app, that means established niche player.
Track changes month-over-month in the Performance section below: live snapshot history and revenue forecast included.
📊 Performance Tracking LIVE
Loading…
Rating
—
Reviews
—
Forecast Revenue / mo
—
Snapshots tracked
0
since first record
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 6 of 6 triggers
Our ML model uses 200+ signals from public data. These are the most influential for this app:
| Paid app ($6.99)METRIC | +$2,800 | |
| Excellent rating (5.0★)METRIC | +$2,200 | |
| excellent appREVIEW | +$1,500 | |
| Mature app (13y old)METRIC | +$1,500 | |
| Single-language (English only)METRIC | −$400 | |
| Pre-traction phase (33 ratings)METRIC | −$300 |
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 →💾 3 MB🔞 4+📱 iOS 12.4+🔖 v3.5.4🔄 updated 2y ago🌐 EN📂 Productivity💰 Paid🚀 Launched 2012 (13y old)
📝 About this app
RPN 28x Calc is a programmable scientific calculator with a pleasingly classic look. Despite its nostalgic appearance, it offers a modern and intuitive user experience, allowing you to interact with your operands by touching them in the display.
It is a reverse-polish notation (RPN) calculator with a dynamic stack display. As you add more values to the stack, the display shown on an iPad automatically expands. To see more lines, simply swipe to scroll. You can also re-order the levels or modify any of the values on the stack.
-----… View full description on the official store →
It is a reverse-polish notation (RPN) calculator with a dynamic stack display. As you add more values to the stack, the display shown on an iPad automatically expands. To see more lines, simply swipe to scroll. You can also re-order the levels or modify any of the values on the stack.
-----… View full description on the official store →
🆕 What's New · v3.5.4
- Prevents the assistant window from being hidden whan transitioning from Slide Over or Split View into Full Screen mode.
- Corrects the factorial of zero: 0! = 1.
- Corrects the factorial of zero: 0! = 1.
Profile & Insights
Everything we know — and don't — about this app and its company.
Identification
- App name
- RPN 28x Calc
- Developer
- tredje design
- Bundle ID
- se.tredje.Calculator
- App Store URL
- Open in App Store
- Category
- Productivity
- Content rating
- 4+
- Languages
- EN
Company
- Website
- www.tredje.se
- 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
- $8.7K/mo
- Top-grossing rank
- Outside top 100 in US Productivity
- All-time revenue
- Not found
- Pricing
- Not found
Founder
- Name
- Not found
- X / Twitter
- Not found
- Not found
- GitHub
- Not found
- X followers
- Not found
- Public statements
- Not found
Funding
- Total raised
- Not found
- Last round
- Not found
- Investors
- Not found
- Crunchbase
- Not found
- AngelList
- Not found
Press & Links
- Articles found
- Not found
- Listed on
- Not found
- Blog
- Not found
- Press / News
- Not found
Contacts & Socials
- Socials
- Not found
- Not found
- Phone
- Not found
- Contact page
- Not found
- About page
- Not found
⭐Recent App Store Reviews21 latest · avg 4.9★ · 90.5% 5★ · 0% 1★
5★19 (90%)
4★2 (10%)
3★0 (0%)
2★0 (0%)
1★0 (0%)
+0 ratings/week
Praise: great ×8 best ×5 love ×4 favorite ×2 awesome ×2Complaints: broken ×1
Top positive
★★★★★ Nice Job!
The 28C was my first RPN calculator during my undergraduate degree. This app does a great job of emulating that experience. Thx much!…
★★★★★ Who'd have thought...
Great surprise when searching for an RPN calculator application and running across this app which is reminiscent of my HP 28s from years past. Functions great for what I need it for, the adaptation for the IPad is great! Kudos to the auth…
Top negative
★★★★☆ Powerful & Easy to Use
If you're comfortable with rpn (reverse polish notation), this is an excellent app. It may be overkill for the average joe, but this is reminiscent of my 48GX calculator, used back in engineering school, without the graphics/plotting i…
★★★★☆ Good app, some room for improvement
Nice app, very accurate emulator, except for the fact that it doesn't support programming, which is still a major drawback. Once you add this functionality, you will see sales go up significantly…
📈Ratings growth33 ratings+3200% lifetimeShow 3-year history estimate ▾
Tracked (23 weeks) Pre-tracking estimate (36 weeks) · model-based, ±5% noise · anchored to release date and current value
🌍Geographic ReachNot ranked
This app is currently outside the top 100 grossing in all 9 countries we monitor (US, UK, DE, FR, JP, CA, AU, BR, IN). Niche or new apps often launch this way — popularity rankings appear once daily revenue clears the regional threshold.
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.
Full revenue analysis
Read the article-style breakdown for RPN 28x Calc: category rank, percentile, growth signal, comparable apps, and how the forecast is calibrated against verified-MRR anchors in this niche.