Petal Layout Pro vs Retrotype
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
Petal Layout Pro
This app assists in the fabrication of spherical and hemispherical heads by calculating precise petal layouts. It supports various part divisions for accurate flat pattern development, ideal for pressure vessel and storage tank construction.
- Sphere petal layout calculation
- Hemispherical head petal layout calculation
- Multiple part divisions (12, 24, 48)
- Unit setting for mm/inches
- Flat pattern development
- Supports pressure vessel fabrication
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Petal Layout is a professional fabrication calculator for developing petal-type layouts for spheres and hemispherical heads. It is designed for pressure vessel fabrication, process equipment manufacturing, spherical tank fabrication, and industrial sheet metal work. The app generates fabrication-ready layout dimensions that can be used for marking plates or sheet metal before cutting, forming, and assembling spherical or hemispherical components. Whether you are a fabrication engineer, fitter, workshop technician, production engineer, or pressure vessel professional, Petal Layout helps simplify complex petal development calculations and improves accuracy during fabrication. Supported Petal Layouts • Hemispherical Head / Hemi Head • Hemispherical Dish End • Sphere / Spherical Tank Hemispherical Head Petal Layout Generate petal development dimensions for hemispherical pressure vessel heads and dish ends. Enter the required head diameter and straight face length, select the desired number of development divisions, and calculate the layout dimensions required for plate marking. Sphere Petal Layout Generate petal-type development dimensions for spherical tanks and spherical shells. Enter the sphere diameter and select the required number of divisions to generate the layout dimensions for fabrication. Development Options Choose from predefined development divisions: • 12 Parts • 24 Parts • 36 Parts • 48 Parts You can also enter a custom number of development divisions according to your fabrication requirements. Features • Sphere petal layout development • Hemispherical head petal development • Dish end petal layout • Spherical tank layout calculations • Multiple development division options • Custom development line/part count • Fabrication-ready marking dimensions • Clear and easy-to-understand results • Simple professional interface • Metric and Imperial unit support • No internet connection required Fabrication Applications Petal Layout is useful for: • Pressure Vessel Fabrication • Spherical Tank Fabrication • Process Equipment Fabrication • Storage Tank Manufacturing • Dish End Fabrication • Hemispherical Head Fabrication • Sheet Metal Fabrication • Industrial Fabrication • Plate Layout and Marking Designed For • Fabrication Engineers • Fabrication Fitters • Production Engineers • Mechanical Engineers • Workshop Technicians • Pressure Vessel Fabricators • Tank Fabricators • Process Equipment Manufacturers • Fabrication Supervisors • Engineering Students For improved fabrication accuracy, the app can be used with appropriate mean dimensions when developing and marking petal layouts. Petal Layout provides a convenient solution for generating sphere and hemispherical head petal development dimensions, helping reduce manual calculations, save fabrication time, and improve accuracy during plate layout and marking.
Retrotype
Experience the satisfying feel of a classic typewriter on your device. Choose from multiple vintage models, customize sounds and visuals, and enjoy distraction-free writing with authentic haptic and audio feedback.
- Authentic typewriter models
- Customizable sound packs
- Haptic feedback
- Multiple color palettes and paper themes
- External keyboard support
- Distraction-free writing environment
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Rediscover the joy of writing without distractions. Retrotype transforms your device into a beautiful, tactile typewriter — complete with the sounds, rhythm, and charm of the classics. CHOOSE YOUR MACHINE Four meticulously crafted typewriter models, each with a distinct personality: - Clean, timeless design. The one that started it all. - Vintage European style with warm, earthy tones. - Mid-century curves in playful pastel palettes. - Bold industrial form with exposed ribbon cartridges. MAKE IT YOURS 22+ hand-picked color palettes. 12 paper themes. 5 authentic sound packs — from the sharp snap of a classic to the soft press of a modern electric. Dial in your haptics, adjust your margins, and set your bell. FEEL EVERY KEYSTROKE Authentic sound and haptic feedback bring every key press to life. Carriage returns, margin bells, and the steady rhythm of typing pull you into a focused flow. WRITE ANYWHERE Designed for iPhone, iPad, and Mac with seamless external keyboard support. Your documents are always ready. ONE PRICE. EVERYTHING INCLUDED. Retrotype Premium is a single purchase — no subscriptions, no recurring fees. Every model, palette, sound pack, and future update is yours forever. Retrotype is a place to slow down, find your flow, and let words unfold one keystroke at a time.
Screenshots
Verdict
The clearest difference is review sentiment: Retrotype at 86% against Petal Layout Pro's 0%. Retrotype also leads on price (Free vs $3.99) and update cadence (every 3 months vs every 41 months). Petal Layout Pro's advantage is in-app purchases (none vs 1). On ads, monetization model, 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
Retrotype is free to download; Petal Layout Pro costs $3.99 up front. Retrotype sells 1 one-off in-app purchase. Petal Layout Pro asks for nothing beyond the download.
Petal Layout Pro ships an update every 41 months, Retrotype every 3 months. The most recent releases landed on October 1, 2026 and October 7, 2026 respectively.
| Parameter | Petal Layout Pro | Retrotype |
|---|---|---|
| Price | $3.99 | Free — better |
| Rating | — | 4.3 (6 ratings) — better |
| Positive reviews | 0.0% of reviews | 85.7% of reviews — better |
| Number of ratings | — | 6 — better |
| Update frequency | Every 41 months | Every 3 months — better |
| Ads | No | No |
| In-app purchases | No — better | Yes |
| Monetization | Paid | Paid |
| Devices | iPhone, iPad | iPhone, iPad, iPod — better |
| Requires iOS | 16.1 | 15.1 — better |
| Further details — not scored | ||
| Size | 1 MB | 27 MB |
| Age rating | 4+ | 4+ |
| Developer | Imran Pinjara | Good Loop Software LLC |
Customer experience
Petal Layout Pro
Retrotype
In-app purchases
Petal Layout Pro
No in-app purchases
Retrotype
- Unlock Everything$4.99









