Comparison

LeftRightDiary vs Book Isle

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

Head to head
About

LeftRightDiary

This app allows you to record life's moments using text and images, with support for Markdown editing. It prioritizes privacy by storing all data locally on your device and offers various ways to review past entries.

Highlights
  • Markdown and Rich Text editing
  • Mixed text and image layout
  • Heatmap and Calendar views
  • Random memory recall
  • Local data storage
  • WebDAV and Alibaba Cloud Disk sync
Features
Read full description

**Capture Every Moment** With Zuoyou Diary, record every moment of your life! 【Product Introduction】 Zuoyou Diary is a simple and pure diary app! It supports writing journals in Markdown, combining text and images. All basic features are completely free. All diary data is stored only on your device — your privacy is our top priority, so you never have to worry about data leaks. In addition, you can easily review past entries through various views such as Heatmap, Calendar, Random Recall, and "On This Day in the Past." Everything is clearly laid out so you can effortlessly keep track of life's little moments. 【Key Features】 * Supports both Markdown and Rich Text editors * Mixed text and image layout * Heatmap support * Calendar view (with heatmap) * Calendar image view * On this day in the past * Random memory recall * Privacy-focused: data stored locally on your device * Sync via WebDAV * Sync with Alibaba Cloud Disk

About

Book Isle

This app allows you to connect to your personal NAS, WebDAV, SMB, OPDS, or Calibre library to import, browse, search, download, and read local and remote books. It supports a wide range of file formats and offers a robust local reading experience with features like full-text search and highlighting.

Highlights
  • Connect to NAS, WebDAV, SMB, OPDS, Calibre
  • Import and manage multiple book formats
  • Full-text search and bookmarking
  • Remote reading and downloading
  • Private synchronization of reading progress
  • Face ID app lock for privacy
Features
Read full description

Book Isle is an e-book reader designed for personal private libraries. You can connect your iPhone and iPad to your own NAS, WebDAV, SMB, OPDS, or Calibre library, import, browse, search, download, and read local and remote books. The app does not provide an online bookstore, does not host or distribute book content, and your book files are still managed by your local device or your own private library. Main functions: - Private library connection: Supports WebDAV, SMB, OPDS, Calibre Content Server, and Calibre metadata.db. - Multi-format bookshelf: Supports the import, management, and reading of TXT, EPUB, PDF, Markdown, HTML, FB2, RTF, DOCX, CBZ, and common audiobook formats; MOBI, AZW, AZW3, CBR, DJVU can be imported, managed, filtered, and synchronized. It is recommended to convert them to EPUB, PDF, or CBZ for reading. - Local reading experience: Supports bookshelf grid/list, sorting, tagging, rating, reading status, full-text search, bookmarking, notes, highlighting, book excerpt cards, and reading statistics. - Remote reading and downloading: Browse private libraries from NAS, OPDS, or Calibre, download or stream supported book formats on demand. - Private synchronization: Synchronize reading progress, book metadata, notes, highlights, tags, reading statistics, and reading settings through the WebDAV directory you have configured. - Privacy and security: No self-built account system; supports Face ID app lock; book files will not be automatically uploaded to our servers due to synchronization function. ShuYu is suitable for readers who already have NAS, Calibre, WebDAV directories, or OPDS book sources, allowing them to manage their private book collections with a quiet and reliable reader. Subscription and purchase instructions: Bibliophile Pro offers monthly and annual memberships with automatic renewal, as well as a one-time purchase for a permanent membership. After activation, users can enjoy member-only features such as browsing, searching, downloading, and remote reading of private libraries via NAS/WebDAV/SMB, OPDS, Calibre, as well as private WebDAV synchronization. Monthly and annual memberships are auto-renewable subscriptions on the App Store. After confirming your purchase, the fee will be deducted from your Apple ID account; the subscription will automatically renew before the end of the current period, unless you turn off auto-renewal at least 24 hours before the end of the current subscription period; the renewal fee will be confirmed and deducted by Apple within 24 hours before the end of the current period. You can manage or cancel your subscription in iOS Settings > Apple ID > Subscriptions, or open the App Store subscription management page from the in-app membership page. After canceling your subscription, you can still use the membership benefits until the end of the current paid period. The actual price, trial, promotions, and available items are subject to the display on the App Store purchase confirmation page. Refunds are processed by Apple according to its rules. After membership expires, is cancelled, is refunded, or the transaction is revoked, the remote library and private sync features that require membership will be locked; downloaded books, local reading, local notes, and local shelf management can still be used. The specific agreement is as follows: Terms: https://sobison.github.io/nasbook/auto-renewable-subscription-terms.html membership: https://sobison.github.io/nasbook/membership-agreement.html Privacy: https://sobison.github.io/nasbook/privacy-policy.html

Screenshots

LeftRightDiary4 screens
Book Isle4 screens

Verdict

The call

The clearest difference is price: LeftRightDiary at Free against Book Isle's $0.99. Book Isle's advantage is review sentiment (89% vs 50%) and update cadence (weekly vs monthly). On rating, ratings volume, 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

LeftRightDiary is free to download; Book Isle costs $0.99 up front. LeftRightDiary sells 3 one-off in-app purchases and Book Isle sells 3 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 5.0 for LeftRightDiary against 5.0 for Book Isle. Both are backed by a comparable volume of ratings — 1 and 2 respectively. Written reviews are what separate them: 50% of LeftRightDiary's written reviews are positive against 89% of Book Isle's.

UpkeepUpdate frequency

LeftRightDiary ships an update monthly, Book Isle weekly. Both last shipped on October 24, 2026.

Scorecard3 real differences · 7 level
LeftRightDiary versus Book Isle: the parameters behind the verdict, then further details
ParameterLeftRightDiaryBook Isle
PriceFree — better$0.99
Rating5.0 (1 ratings)5.0 (2 ratings)
Positive reviews50.0% of reviews89.2% of reviews — better
Number of ratings12 — better
Update frequencyMonthlyWeekly — better
AdsNoNo
In-app purchasesYesYes
MonetizationFree with in-app purchasesFree with in-app purchases
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.0 — better15.6
Further details — not scored
Size80 MB50 MB
Age rating4+9+
Developer候军 袁Anyi County Bingzhiyi Trading Co., Ltd.

Customer experience

LeftRightDiary

All ratings1 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews2 reviews
Positive50.0%
Neutral0.0%
Negative50.0%

Book Isle

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews37 reviews
Positive89.2%
Neutral5.4%
Negative5.4%

In-app purchases

3 purchases

LeftRightDiary

One-time3
  • Upgrade to PRO$3.99
  • 请作者吃大餐$9.99
  • 大力支持$29.99
3 purchases

Book Isle

Subscriptions2
  • Monthly membership$0.991 Month
  • Annual Membership$2.991 Year
One-time1
  • Permanent member$7.99

Questions

Is LeftRightDiary free?
LeftRightDiary is free to download, with in-app purchases available.
Is Book Isle free?
Book Isle costs $0.99, and also offers in-app purchases.
Which has better reviews, LeftRightDiary or Book Isle?
LeftRightDiary and Book Isle are both rated 5.0 out of 5 on the App Store, from 1 and 2 ratings respectively.
Do LeftRightDiary or Book Isle have ads?
Neither LeftRightDiary nor Book Isle shows ads.
Which is updated more often, LeftRightDiary or Book Isle?
LeftRightDiary ships an update monthly, and Book Isle weekly. Most recently, LeftRightDiary was updated on October 24, 2026 and Book Isle on October 24, 2026.

Other comparisons