BlackBox vs Flowdia Diagrams
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
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.
- Collect user-generated text
- Add entries with swipe gesture
- Organize text snippets
- Store fortunes and quotes
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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!
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.
- 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
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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
Verdict
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
Both are free to download. Flowdia Diagrams sells 1 one-off in-app purchase. BlackBox asks for nothing beyond the download.
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.
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.
| Parameter | BlackBox | Flowdia Diagrams |
|---|---|---|
| Price | Free | Free |
| Rating | 4.6 (9 ratings) — better | 3.4 (67 ratings) |
| Positive reviews | 100.0% of reviews — better | 54.2% of reviews |
| Number of ratings | 9 | 67 — better |
| Update frequency | Every 9 months | Every 2 weeks — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Free — better | Free with in-app purchases |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 16.0 | 15.0 — better |
| Further details — not scored | ||
| Size | 4 MB | 24 MB |
| Age rating | 4+ | 4+ |
| Developer | Brian Daneshgar | Behzad Gorimar |
Customer experience
BlackBox
Flowdia Diagrams
In-app purchases
BlackBox
No in-app purchases
Flowdia Diagrams
- Upgrade to Premium$9.99









