Comparison

CogniLog vs Calcium Text Calculator

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

Head to head
About

CogniLog

This app helps you document your work, capturing decisions and reasoning. It allows an AI assistant to read your log and answer questions about your past activities. Entries are plain text with Markdown support, and a visual almanac helps you navigate your history.

Highlights
  • AI-powered work log analysis
  • Plain text entries with Markdown
  • Visual almanac for historical navigation
  • Project-based channels and #tags
  • Cross-device sync via iCloud
  • Import from other note-taking apps
Features
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CogniLog is a work log you can read at any distance. In the Almanac view, step back to the year to see which weeks went to which projects, open a week to skim a few lines from each entry, then tap one to read the whole thing. You write the way you normally would, and CogniLog works out the short versions for each view. If you work with AI agents, they can read and write to the same log, so you and your agents work from the same record. On a Mac, an assistant like Claude, or a coding agent like Claude Code or Codex, connects to CogniLog's built-in MCP server. It can look up your past work, answer questions about it, and log what it did and why. Those entries sync to your iPhone, right next to yours. It fits any kind of work. People use it for code, client projects, research, writing and school. On iPhone Write an entry in the app, from a Lock Screen or Home Screen widget, from the share sheet, or with Siri and Shortcuts. Entries are plain text with light Markdown that formats as you type. Add a #tag and the entry is tagged. Channels keep separate projects apart. You can ask for things back, too. Say "What did I log today in CogniLog" and Siri lists your entries. In Shortcuts you can pull up entries by day, week, channel or tag, search the whole log, or hand a week of entries to Apple Intelligence for a summary. (Summaries need a device that supports Apple Intelligence.) The Almanac view shows your log by week, month and year. Tap a day to see what happened, then open any entry. On iPhone Duo, CogniLog uses both sides of the fold, with your log on one side and your filters or the editor on the other. On Mac CogniLog for Mac uses the same log, synced through your iCloud, and it can do more: • The Almanac view fits a whole year on one screen. Hover over a day for a summary of what happened. • Import from apps like Apple Notes, Day One, Obsidian and Bear, or from a folder of Markdown files, and export everything back out as Markdown whenever you want. • The built-in MCP server lets your AI assistants read your log and write to it. • Log from the menu bar or from Spotlight without switching away from what you're doing. If you have a Mac, get CogniLog there too. Your iPhone and your Mac write to the same log. Privacy Your entries stay on your devices and in your own iCloud. The app sends anonymous usage counts that never include anything you write and aren't linked to you. About CogniLog is made by Rivet & Rune. Questions, bugs and ideas go to support@rivetrune.com, and each one gets read.

About

Calcium Text Calculator

Features
Read full description

Calcium is a text editor that updates math results as you type. Use `=>` to compute expressions. It supports all kinds of units. Best of all, it's free and open source!

Screenshots

CogniLog4 screens
Calcium Text Calculator2 screens

Verdict

The call

The clearest difference is update cadence: Calcium Text Calculator at every 5 days against CogniLog's every 2 weeks. Calcium Text Calculator also leads on iOS requirement (17.0 vs 26.2). On price, 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

CogniLog ships an update every 2 weeks, Calcium Text Calculator every 5 days. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
CogniLog versus Calcium Text Calculator: the parameters behind the verdict, then further details
ParameterCogniLogCalcium Text Calculator
PriceFreeFree
Rating5.0 (3 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings3 — better—
Update frequencyEvery 2 weeksEvery 5 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationFree—
DevicesiPhone, MaciPhone, iPad, Mac — better
Requires iOS26.217.0 — better
Further details — not scored
Size53 MB3 MB
Age rating4+4+
DeveloperRivet Rune LLCTwarge LLC

In-app purchases

None

CogniLog

No in-app purchases

None

Calcium Text Calculator

No in-app purchases

Questions

Is CogniLog free?
CogniLog is free to download, with no in-app purchases.
Is Calcium Text Calculator free?
Calcium Text Calculator is free to download, with no in-app purchases.
Do CogniLog or Calcium Text Calculator have ads?
Neither CogniLog nor Calcium Text Calculator shows ads.
Which is updated more often, CogniLog or Calcium Text Calculator?
CogniLog ships an update every 2 weeks, and Calcium Text Calculator every 5 days. Most recently, CogniLog was updated on November 5, 2026 and Calcium Text Calculator on October 31, 2026.

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