Comparison

Kuna vs Dioptra

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

Head to head
About

Kuna

This app helps you manage tasks and projects with features like priorities, due dates, and custom labels. It facilitates collaboration through comments and integrates with your calendar for seamless scheduling and reminders.

Highlights
  • Task organization with priorities and due dates
  • Customizable labels for workflow matching
  • Assignees, reminders, and scheduling
  • Dependency management
  • Team collaboration via comments
  • Calendar sync
  • Flexible display options
Features
Read full description

Kuna is a modern task manager for Vikunja — built for clarity, collaboration, and control. Organize projects, track tasks with priorities and due dates, and customize labels to match your workflow. Plan every detail with assignees, reminders, and scheduling. Manage dependencies so nothing slips through the cracks, collaborate with teammates through comments, and sync tasks with your calendar. Personalize your view with flexible display options and stay on top of your work — wherever you go.

About

Dioptra

Features
Read full description

A 3D model viewer for iPhone and iPad that takes measurement seriously. Open a file, turn it over, and tap two points on the surface to get a real distance. FORMATS • glTF — .glb and .gltf • USD — .usdz, .usdc, .usda and .usd • STL — 3D prints and CAD exports, read in millimetres and turned upright • PLY — scans and photogrammetry, with per-vertex colour • VRM • Interactive pages — an .html export keeps its own controls and runs as it was built MEASURE • Tap two points for a true distance • Take as many measurements as you need; they stay listed with the model • Switch between metric and imperial whenever you like • Set what one file unit means: metres, centimetres, millimetres, inches or feet INSPECT • Orbit, pan and zoom, or leave it turning on its own • Wireframe, to see how a mesh is built • Studio, light and dark backgrounds • Play embedded animations, one clip at a time • Model info: width, height and depth, plus triangles, vertices, meshes, materials, textures, nodes and animations • Share a snapshot of the view ORGANISE • Folders, which appear in the Files app exactly as they do here • Search, sort by name, type or date, and switch between a list and a grid • Rename, drag a model onto a folder to file it, or delete it • Bring models in with the picker, from another app's share sheet, or by dropping them into the Dioptra folder in Files SAMPLES Six models come with the app, one for each kind of file it opens, all built to real-world scale: the ancient sighting instrument the app is named for, a Roman surveyor's groma, a sundial's gnomon, a tripod foot in millimetres, a surveyed patch of terrain, and an interactive plan of sight lines. PRIVATE BY DEFAULT No account, no sign-in, no cloud, no tracking and no ads. Your models stay on your device and everything works offline.

Screenshots

Kuna4 screens
Dioptra4 screens

Verdict

The call

The clearest difference is in-app purchases: Kuna at none against Dioptra's 3. On price, update cadence, ads and device support 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. Dioptra sells 3 one-off in-app purchases. Kuna asks for nothing beyond the download.

UpkeepUpdate frequency

Both ship on a similar rhythm, roughly fortnightly. The most recent releases landed on October 24, 2026 and October 26, 2026 respectively.

Scorecard1 real difference · 8 level
Kuna versus Dioptra: the parameters behind the verdict, then further details
ParameterKunaDioptra
PriceFreeFree
Rating5.0 (1 ratings) — better—
Number of ratings1 — better—
Update frequencyFortnightlyFortnightly
AdsNoNo
In-app purchasesNo — betterYes
MonetizationFree—
DevicesiPhone, iPadiPhone, iPad
Requires iOS18.417.0 — better
Further details — not scored
Size30 MB5 MB
Age rating4+4+
DeveloperRICHARD JOHN ANNANDZachary Griffin

In-app purchases

None

Kuna

No in-app purchases

3 purchases

Dioptra

One-time3
  • Small Tip$0.99
  • Tip$1.99
  • Generous Tip$4.99

Questions

Is Kuna free?
Kuna is free to download, with no in-app purchases.
Is Dioptra free?
Dioptra is free to download, with in-app purchases available.
Do Kuna or Dioptra have ads?
Neither Kuna nor Dioptra shows ads.
Which is updated more often, Kuna or Dioptra?
Kuna ships an update fortnightly, and Dioptra fortnightly. Most recently, Kuna was updated on October 24, 2026 and Dioptra on October 26, 2026.

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