CRUMB
by Vital Group Limited
- Productivity
- Paid
- Small & simple · 90
- Rating
- 4.4
- 144 ratings
- Top 80%among 224 Productivity apps
- Last update
- Aug 29, 2022
- Version 1.0.3
- Size
- 520 MB
- Category
- Productivity
- Tracked since
- Oct 10, 2026
Estimated revenue
A model estimate with a likely range, not a reported figure.
No estimate. Apps outside the grossing charts, and some countries, have no reliable rank-to-revenue curve, so we show nothing rather than a guess.
How this estimate is made
Rank: we take the app's best Top Grossing rank on the latest chart day. Category ranks are converted into an equivalent overall rank, because a #10 in Finance earns far less than a #10 overall.
Curve: that equivalent rank is read off a rank-to-revenue curve anchored on public company revenue and market-data reports for the US iPhone App Store.
Country: the curve is scaled per country (Japan is roughly a third of the US, Türkiye under 1%). Where we have no scale, such as China, there is no estimate.
Range: the likely range widens with country, category and chart depth. It is a plausible span, not a statistical confidence interval.
Not included: ads, payments outside the App Store, and any difference between gross sales and what the developer keeps. Low confidence means indirect data; medium means several independent sources agree.
Full methodScreenshots
As shown on the App Store listing.
About this app
Text from the App Store listing.
CRUMB offers an easy to use and interactive introduction to electronic circuits
Fully realised in 3D, you can construct prototype circuits as you would at the workbench without the risk of terminal component failure or the hassle of ordering individual components
CRUMB comes with a great selection of components to allow you to jump straight in to creating prototype circuits
With the catalogue available, it is possible to study the workings of transistors & audio filtering, all the way to programming an EEPROM to run a basic program
For the beginner, it is possible to learn and understand the basics of interactivity, and for the enthusiast it is possible to analyse and perfect prototypes before constructing real world models
Using the built in oscilloscope and analysis views, it is possible to see clearly the interaction between components from within the wires themselves
Through community feedback and suggestion, there will be many more components and features added. For a full feature list and development schedule please visit the website http://www.crumbsim.com
What’s new
Release notes for the latest version, as written by the developer.
Version 1.0.3 Updates:
- Camera touch controls
- Undo/Remove Point functionality when creating wired components
- Breadboards and Power Rail can be snapped together
- The Scope window can now be moved around the screen
Bug Fixes:
- LED and Capacitor bodies now correct orientation on first point
- Power Supply outline after rotation
- LED simulation oscillation fix
Rank history
Daily position in the US charts. #1 is at the top.
- Best rank
- #41
- Current rank
- –
- Days charting
- 3 of 7
Not charting today
On the charts today
Not on any US chart today.
Small & simple score
How realistic it is for a small team to build something like this.
90/100
Small & simple
- Developer size100% · 25
Developer: 1 app on the charts
- Audience size100% · 20
Ratings: 144
- App size0% · 10
Size: 520 MB
- Price model100% · 15
Price model: paid
- Demand proof100% · 30
Best rank #1, 23 countries
An indicator, not a fact. We can't see team size. Calculated Oct 25, 2026 · method i2
How the score worksGap check · UK
Is this US chart app missing in UK?
It showed up on a UK chart in the last 30 days, so it is not a gap.
Store not checked yet
This is a candidate, not a verdict. Charts show at most 100 apps, so not charting does not mean no demand. Check the UK store before you decide.
See all gapsVersion history
- 1.0.3LatestReleased Aug 29, 2022