Comparison

BlackBox vs Flowdia Diagrams

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

BlackBox

A simple app for collecting and organizing user-generated text snippets, like fortunes or insightful quotes. Users can easily add their own entries with a swipe gesture to build a personal collection of interesting text.

Highlights
  • Collect user-generated text
  • Add entries with swipe gesture
  • Organize text snippets
  • Store fortunes and quotes
Features
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User generated text. Swipe up to add an entry! I've always liked keeping fortunes in my phone case. BlackBox contains some of these fortunes, along with other obscure, insightful, interesting text. Swipe up to add your own entry to the collection!

About

Flowdia Diagrams

Create professional flowcharts, mind maps, and various other diagrams with an intuitive interface. Easily connect shapes, add elements, and customize your designs. Export your work in multiple formats, including PNG, JPG, PDF, and SVG.

Highlights
  • Create flowcharts, mind maps, BPMN, and network diagrams
  • Intuitive shape connection and element addition
  • Customizable shape appearance
  • Export to PNG, JPG, PDF, and SVG
  • Import custom images
  • Supports various UML diagram types
Features
Read full description

Flowdia is an easy to use flow diagram tool that can be used to quickly create professional quality flowcharts, mind maps, BPMN, network and server layouts, Cisco network, Rack diagram, UML activity, business process and process flow diagrams. The app is designed with ease of use in mind. You can quickly connect flowchart shapes by simply selecting the start and end connection points and quickly add new lanes to a swimlane diagram or new sub-topics to a mind map diagram by using "+" button from the selected swimlane or mind map shape menu. The mind map sub-topics are automatically positioned on the page but can be easily moved as required. Flowdia supports export of the diagram / flowchart to PNG, JPG, PDF and SVG formats.You can view exported SVG files in Microsoft Visio. You can import custom PNG and JPG images. The following diagrams can be created using Flowdia: - Flowchart - Swimlanes - Mind Maps - BPMN - Network Diagram - AWS Architecture Diagram - Cisco Network Diagram - Server Layout Diagram - Rack Diagram - UML Class Diagram - UML Activity Diagram - UML Use Case Diagram - UML Sequence Diagram - Business Process Diagram - Process Flow - Chevron Diagram You can quickly select and change BPMN activity, event and gateway types by using the special shape selector available to all BPMN shapes. The flowchart shapes in this tool are not images can be re-sized without loosing quality. You can customize the look of the shapes by applying background color and also change the font color and size of the text. **NOTE: Free version of Flowdia is restricted to: - 4 files. - 1 page per diagram. - Cannot remove or duplicate pages. - Image and PDF exports with watermark

Screenshots

BlackBox2 screens
Flowdia Diagrams4 screens

Verdict

The call

The clearest difference is review sentiment: BlackBox at 100% against Flowdia Diagrams's 54%. BlackBox also leads on rating (4.6 vs 3.4) and in-app purchases (none vs 1). Flowdia Diagrams's advantage is update cadence (every 2 weeks vs every 9 months) and ratings volume (67 vs 9). On price, ads, device support and iOS requirement there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Flowdia Diagrams sells 1 one-off in-app purchase. BlackBox asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

BlackBox holds the better App Store score, 4.6 against 3.4. That said, the two scores are not equally well evidenced: Flowdia Diagrams has 67 ratings behind it against 9, so its average is the more settled of the two. Written reviews point the same way: 100% of BlackBox's written reviews are positive against 54% of Flowdia Diagrams's.

UpkeepUpdate frequency

BlackBox ships an update every 9 months, Flowdia Diagrams every 2 weeks. The most recent releases landed on November 1, 2026 and November 11, 2026 respectively.

Scorecard6 real differences · 4 level
BlackBox versus Flowdia Diagrams: the parameters behind the verdict, then further details
ParameterBlackBoxFlowdia Diagrams
PriceFreeFree
Rating4.6 (9 ratings) — better3.4 (67 ratings)
Positive reviews100.0% of reviews — better54.2% of reviews
Number of ratings967 — better
Update frequencyEvery 9 monthsEvery 2 weeks — better
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad, iPod — better
Requires iOS16.015.0 — better
Further details — not scored
Size4 MB24 MB
Age rating4+4+
DeveloperBrian DaneshgarBehzad Gorimar

Customer experience

BlackBox

All ratings9 ratings
Positive77.8%
Neutral22.2%
Negative0.0%
Written reviews3 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Flowdia Diagrams

All ratings66 ratings
Positive57.6%
Neutral10.6%
Negative31.8%
Written reviews142 reviews
Positive54.2%
Neutral14.8%
Negative31.0%

In-app purchases

None

BlackBox

No in-app purchases

1 purchases

Flowdia Diagrams

One-time1
  • Upgrade to Premium$9.99

Questions

Is BlackBox free?
BlackBox is free to download, with no in-app purchases.
Is Flowdia Diagrams free?
Flowdia Diagrams is free to download, with in-app purchases available.
Which has better reviews, BlackBox or Flowdia Diagrams?
BlackBox is rated higher. BlackBox averages 4.6 out of 5 from 9 ratings, while Flowdia Diagrams averages 3.4 from 67 ratings.
Do BlackBox or Flowdia Diagrams have ads?
Neither BlackBox nor Flowdia Diagrams shows ads.
Which is updated more often, BlackBox or Flowdia Diagrams?
BlackBox ships an update every 9 months, and Flowdia Diagrams every 2 weeks. Most recently, BlackBox was updated on November 1, 2026 and Flowdia Diagrams on November 11, 2026.

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