Comparison

AI Writer vs Lux Light Meter

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

Head to head
About

AI Writer

This AI writing assistant generates emails, posts, and replies directly on your device using on-device AI. It offers features like a writing chat for revisions, a reply assistant for understanding messages, and summarization tools. Save, search, and export your creations in various formats.

Highlights
  • On-device AI writing
  • Writing chat for revisions
  • Reply assistant
  • Summarize long texts
  • Template library
  • Personalized writing style
  • Siri and Shortcuts integration
  • Export to Word, Markdown, text
Features
Read full description

AI Writer writes emails, posts, replies and rewrites on your device, with Apple Intelligence. No account, no server, nothing leaves your device. Writing requires Apple Intelligence on a supported device with iOS 26 or later. On other devices your saved texts stay readable. WRITE ANYTHING • Three versions of every text, written live, so you can pick the angle you like • Writing Chat: write something, then ask for changes in your own words. Shorter, warmer, add a deadline. Every version is kept • Emails, posts for X, blog posts, rewrites, continued texts and grammar fixes with a word-by-word diff REPLY AND UNDERSTAND • Reply Assistant: paste a message, get the gist, what needs an answer and three replies • Summarize: a long email or article becomes the key points, what it asks of you and the jargon explained • Meeting notes: rough notes become a summary, decisions and a to-do list with owners and dates TEMPLATES Short messages, out-of-office replies and headlines. Plus: cover letters, job posts, product descriptions, LinkedIn About, review replies and bios. YOUR VOICE Paste a few things you wrote. AI Writer learns your style on your device and writes every text the way you would. Only the style is kept, never your texts. SIRI AND SHORTCUTS Draft a reply, rewrite text or write a post without opening the app. Send any text to AI Writer from the Shortcuts app. YOUR LIBRARY Every text you save gets a title. Search, filter, edit, copy, share, or export as a Word, Markdown or text file. PRIVATE BY DESIGN Everything is written on your device. AI Writer has no account and no server, and it never sees what you write. AI WRITER PLUS Writing is free. Plus adds Pro templates and Meeting notes, unlimited Writing Chat, more voices, your whole library and export. Monthly, yearly, or once for a lifetime. If you ever subscribed to AI Writer before, Plus is free for you, forever. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the period. Manage or cancel in Settings › Apple Account › Subscriptions. Terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy: https://www.termsfeed.com/live/cb1ecc3f-0b1e-4520-9cef-f4aec66e7ca7

About

Lux Light Meter

Measure ambient light levels with your iPhone. Get real-time lux and foot-candle readings, with specialized modes for photography and plant care. Track light history and calibrate for accuracy.

Highlights
  • Ambient light metering (lux/fc)
  • Photography exposure suggestions
  • Plant light (PPFD/DLI) estimation
  • Continuous measurement and history
  • Optional meter calibration
  • Privacy-friendly local storage
Features
Read full description

Lux Light Meter: Illuminance A practical lux and illuminance meter for iPhone. Measure ambient light in seconds, check if a room is bright enough for study, work, or home use, and get helpful exposure and plant-lighting guidance when you need it. Core metering works offline. Key Features: Ambient light metering - Live lux / fc readings with scene targets that tell you if the light is too dim, about right, or too bright — plus simple tips to adjust Photography mode (Pro) - Aperture- or shutter-priority suggestions with ISO and exposure compensation so you can dial in exposure faster Plant mode (Pro) - Estimate PPFD and DLI for common houseplants, with light source and daily photoperiod options Continuous measure & history - Save single readings, track how light changes over time, and review min, average, and max values Optional calibration - Fine-tune against a trusted meter; Pro saves separate factors for the front and rear cameras Units & privacy-friendly storage - Switch between lux and fc; your measurements stay on your device How to Use: Open the app, allow camera access, and point your iPhone at the area you want to measure. Switch between Environment, Photography, and Plant modes, then save a reading or run a continuous measurement when you need a longer sample. Subscription Options: * Weekly and yearly subscriptions, plus a lifetime purchase * Payment will be charged to your Apple ID account * Subscriptions renew automatically within 24 hours before the current period ends * Manage or cancel anytime in your Account Settings Clearer readings. Better light decisions. Terms of Use: https://lightmeter.xzonesoft.com/terms.html Privacy Policy: https://lightmeter.xzonesoft.com/privacy.html Contact Us: support@xzonesoft.com

Screenshots

AI Writer4 screens
Lux Light Meter3 screens

Verdict

The call

The clearest difference is review sentiment: Lux Light Meter at 100% against AI Writer's 54%. Lux Light Meter also leads on rating (5.0 vs 4.3). AI Writer's advantage is ratings volume (125 vs 5). On price, update cadence, ads and in-app purchases 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. AI Writer sells 3 in-app purchases, starting at $3.99 per month and Lux Light Meter sells 3 in-app purchases, starting at $1.99 per 7 days. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

Lux Light Meter holds the better App Store score, 5.0 against 4.3. That said, the two scores are not equally well evidenced: AI Writer has 125 ratings behind it against 5, so its average is the more settled of the two. Written reviews point the same way: 54% of AI Writer's written reviews are positive against 100% of Lux Light Meter's.

UpkeepUpdate frequency

AI Writer ships an update every 8 days, Lux Light Meter fortnightly. The most recent releases landed on November 7, 2026 and November 5, 2026 respectively.

Scorecard3 real differences · 7 level
AI Writer versus Lux Light Meter: the parameters behind the verdict, then further details
ParameterAI WriterLux Light Meter
PriceFreeFree
Rating4.3 (125 ratings)5.0 (5 ratings) — better
Positive reviews54.3% of reviews100.0% of reviews — better
Number of ratings125 — better5
Update frequencyEvery 8 days — betterFortnightly
AdsNoNo
In-app purchasesYesYes
MonetizationFreemiumFree with in-app purchases
DevicesiPhone, iPadiPhone, iPad
Requires iOS16.0 — better17
Further details — not scored
Size26 MB4 MB
Age rating4+4+
DeveloperAndras Molnar灿耿 陈

Customer experience

AI Writer

All ratings125 ratings
Positive78.4%
Neutral5.6%
Negative16.0%
Written reviews35 reviews
Positive54.3%
Neutral8.6%
Negative37.1%

Lux Light Meter

All ratings5 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

AI Writer

Reported bugs

13 issues
  • App doesn't generate articles
  • Key is invalid after generation
  • Help request errors
  • "Something went wrong" error message
  • API key not working
Show 8 more
  • Internet access error message
  • App doesn't work at all
  • Keeps saying API key doesn't work
  • Asking for a key without explanation
  • App failed first time, API error
  • API is not working
  • Too many steps to use API key
  • Doesn't generate content beyond a period

Requested features

2 requests
  • Make the app free or more affordable
  • Provide clear instructions on obtaining API keys

Lux Light Meter

Not enough reviews yet to summarise bugs or requests.

In-app purchases

3 purchases

AI Writer

Subscriptions2
  • Plus Monthly$3.991 Month
  • Plus Yearly$19.991 Year
One-time1
  • Plus Lifetime$49.99
3 purchases

Lux Light Meter

Subscriptions2
  • Weekly Access$1.997 Days
  • Annual Subscription$7.991 Year
One-time1
  • Lifetime Access$12.99

Questions

Is AI Writer free?
AI Writer is free to download, with in-app purchases available.
Is Lux Light Meter free?
Lux Light Meter is free to download, with in-app purchases available.
Which has better reviews, AI Writer or Lux Light Meter?
Lux Light Meter is rated higher. AI Writer averages 4.3 out of 5 from 125 ratings, while Lux Light Meter averages 5.0 from 5 ratings.
Do AI Writer or Lux Light Meter have ads?
Neither AI Writer nor Lux Light Meter shows ads.
Which is updated more often, AI Writer or Lux Light Meter?
AI Writer ships an update every 8 days, and Lux Light Meter fortnightly. Most recently, AI Writer was updated on November 7, 2026 and Lux Light Meter on November 5, 2026.

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