Comparison

OpenTime vs Marklens

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

Head to head
About

OpenTime

Quickly find your open time slots by analyzing your device calendars. This app offers flexible date range views, slot duration selection, and convenient sharing options without requiring accounts or tracking your data.

Highlights
  • View free/busy slots for any date range
  • Slot duration picker with chip subdivision
  • Quick sharing of daily availability
  • Customizable appearance (light/dark/system)
  • Pinned queries for one-tap access
  • Home screen widgets and Live Activities
  • Apple Watch companion app
Features
Read full description

Quickly see when you're free. Open Time reads your device calendars and shows your open time slots. No accounts, no servers, no tracking. FEATURES - View free and busy slots for today, tomorrow, or any date range - Choose which calendars count: exclude holidays, sports schedules, or shared calendars, and every list, widget, and share reflects only the calendars you pick - Slot duration picker (15, 30, or 60 minutes). Chips subdivide your free blocks at the chosen interval - Long-press any chip for Open in Calendar, Create Event Here, or Copy Time - Long-press any day name to Share or Copy that day's availability to anywhere (Messages, Mail, Notes) - Light, dark, or system appearance with an in-app picker - Pull to refresh, and availability refreshes automatically after you create or edit an event - Show or hide busy events - Toggle weekends on or off - This Week, Next Week, and Next 14 Days quick picks - Custom date range picker - Home screen widgets (small and medium). Tap any chip to jump straight to that slot in the app - Live Activities and Dynamic Island for real-time free/busy on your lock screen - Apple Intelligence query bar on supported devices: type "tomorrow afternoon for 30 min" or "any hour Friday afternoon" and get the matching slots - Siri and Shortcuts: try "What's my availability in Open Time" or "When am I free in Open Time" - Apple Watch companion to check your week from your wrist - Share Extension to drop your availability into any app from the share sheet - iMessage app to pick days and send your availability without leaving the conversation PRIVACY FIRST Your calendar data stays on your device. No accounts. No analytics. No third-party servers. Zero data collection. Open Time uses Apple's EventKit to read your calendars locally. Nothing ever leaves your device. Perfect for freelancers, consultants, and anyone who needs to quickly share when they're available.

About

Marklens

This app is a fast, native Markdown viewer for macOS, iPadOS, and iPhone. It renders .md files instantly with beautiful typography, themes, syntax highlighting, and diagrams. Designed for reading, it offers a private and friction-free experience.

Highlights
  • Instant Markdown rendering
  • Syntax highlighting for 30+ languages
  • Mermaid diagram support
  • GitHub-Flavored Markdown
  • Light and dark themes
  • Export to PDF
  • Quick Look preview on macOS
Features
Read full description

Marklens is a fast, native Markdown viewer for macOS, iPadOS, and iPhone. Open any .md file with a click and see it rendered immediately — beautiful typography, light and dark themes, syntax-highlighted code, and Mermaid diagrams. No editor, no library, no friction. HIGHLIGHTS • Instant render — every .md opens in a clean, focused window • 30+ language syntax highlighting via highlight.js, bundled offline • Mermaid 11 diagrams — flowcharts, sequence, state, xy-charts and more • GitHub-Flavored Markdown — tables, task lists, footnotes, strikethrough • Light and dark theme matching the system appearance • Quick Look on macOS — press Space on any .md in Finder for a rendered preview • Export to PDF on every platform • Pinch-to-zoom on iPadOS and iPhone, ⌘+ / ⌘− / ⌘0 on macOS • Open files via drag-and-drop, the Share Sheet, or the Files app MADE FOR READING Marklens doesn't try to be a notes app or a knowledge base. It opens a file, renders it perfectly, and gets out of the way. If you write Markdown in another tool — VS Code, Obsidian, GitHub, your favorite text editor — Marklens is the viewer you reach for to look at the result. PRIVATE BY DESIGN Marklens collects nothing. No analytics, no telemetry, no crash reports, no network requests. Every rendering asset — Mermaid, highlight.js, fonts — ships inside the app. Read the full privacy policy at https://donald-jackson.github.io/marklens/privacy/ OPEN SOURCE Marklens is MIT-licensed and developed in the open. Source, issues, and contribution guide live at https://github.com/donald-jackson/marklens.

Screenshots

OpenTime4 screens
Marklens3 screens

Verdict

The call

The clearest difference is price: Marklens at Free against OpenTime's $0.99. Marklens also leads on ratings volume (3 vs 1) and iOS requirement (18.0 vs 26.2). OpenTime's advantage is update cadence (every 2 days vs monthly). On rating, ads, in-app purchases 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

Marklens is free to download; OpenTime costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for OpenTime against 5.0 for Marklens. Both are backed by a comparable volume of ratings — 1 and 3 respectively.

UpkeepUpdate frequency

OpenTime ships an update every 2 days, Marklens monthly. Both last shipped on October 24, 2026.

Scorecard5 real differences · 5 level
OpenTime versus Marklens: the parameters behind the verdict, then further details
ParameterOpenTimeMarklens
Price$0.99Free — better
Rating5.0 (1 ratings)5.0 (3 ratings)
Positive reviews—0.0% of reviews
Number of ratings13 — better
Update frequencyEvery 2 days — betterMonthly
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPad, Apple WatchiPhone, iPad, Mac
Requires iOS26.218.0 — better
Further details — not scored
Size4 MB4 MB
Age rating4+4+
Developerjames tannahillDonald Jackson

Customer experience

OpenTime

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Marklens

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews1 reviews
Positive0.0%
Neutral100.0%
Negative0.0%

In-app purchases

None

OpenTime

No in-app purchases

None

Marklens

No in-app purchases

Questions

Is OpenTime free?
OpenTime costs $0.99, with no in-app purchases.
Is Marklens free?
Marklens is free to download, with no in-app purchases.
Which has better reviews, OpenTime or Marklens?
OpenTime and Marklens are both rated 5.0 out of 5 on the App Store, from 1 and 3 ratings respectively.
Do OpenTime or Marklens have ads?
Neither OpenTime nor Marklens shows ads.
Which is updated more often, OpenTime or Marklens?
OpenTime ships an update every 2 days, and Marklens monthly. Most recently, OpenTime was updated on October 24, 2026 and Marklens on October 24, 2026.

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