Comparison

PPAS eReader vs Stacks

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

Head to head
About

PPAS eReader

Features
Read full description

PPAS e-Reader is an application that allows members of Raja Tun Uda Library, Shah Alam, and Selangor Public Libraries under Selangor State Government, to borrow e-books of many categories and languages.

About

Stacks

Digitally catalog your physical book collection by simply photographing your shelves. The app automatically identifies titles, authors, and covers, then organizes your library with smart sorting and insightful analytics. Never forget if you own a book or who borrowed it again.

Highlights
  • Scan entire bookshelves with one photo
  • Automatic book identification (title, author, cover)
  • Visual library display with spine width and color
  • Smart sorting by author, genre, or color
  • Track lent books and borrower information
  • Personalized reading recommendations based on owned books
  • AI-powered book concierge for recommendations and discussions
Features
Read full description

Your shelves, in your pocket. Catalog every book you own, then keep track of what you read. Photograph a shelf, scan barcodes, or import your Goodreads or StoryGraph library — your whole collection is with you everywhere, on iPhone and iPad. BUILD YOUR LIBRARY YOUR WAY • Shelf scan: one photo catalogs an entire shelf — 20, 30, 40 books at once • Barcode auto-add: scan, hear the beep, move to the next book — with undo if you catch a wrong one • Import from Goodreads or StoryGraph with a CSV export, and export your library back out any time • Real cover art, page counts, and publication years fill in automatically • Honest AI: spines it can't read are flagged with their position, never guessed TRACK YOUR READING • Mark each book Not started, Reading, Read, or Didn't finish, with start and finish dates • A Currently reading row and a Reading shelf keep what you're in the middle of up front • Set a yearly reading goal and see your pace for the year (Pro) A LIBRARY THAT LOOKS LIKE A LIBRARY • The Shelf view renders your books as actual spines — width from page count, color from the real cover • Sort by author, genre, or color: your shelves as a rainbow • Grid and list views, search, and smart shelves: Unread, Favorites, Lent Out SCOUT SHELVES & BUILD A WISHLIST • Scout mode: point your camera at a bookstore or thrift-shop shelf and see which books fit your taste — before you buy • Librarian's picks (Pro): curated recommendations you can browse by category or search across the whole catalog • Add any book to your Library or your Want list in a tap — from picks, a scout, or a search KNOW YOUR OWN TASTE • Every scan reads your shelf and tells you something true about your taste • "Read next" picks come from books you already own — starting with your unread pile • Insights: pages owned, top genres, most-shelved authors, books added over time DESIGNED FOR IPHONE & IPAD • On iPad: a sidebar, multi-column shelves, and a two-page book view that fills the screen • Portrait or landscape, with Split View and Stage Manager • Your library and Want list stay in sync across devices NEVER LOSE A BOOK AGAIN • Standing in a bookstore wondering if you own it? Search your library in a second • The lending tracker remembers who borrowed what, and since when • Rate, track what you're reading, and keep notes on every book YOUR LIBRARIAN (PRO) • A weekly note on what to start next — from your own unread shelves, with the reasons • Picks chosen for your shelves: real books you don't own yet, tuned to what you've loved • A book-loving AI that knows your entire library: what to read, buy, or gift — grounded in your actual shelves, not bestseller lists • Chat with any single book, in its own voice • Share a Shelfie: your library as a story card — rainbow shelf, reading fingerprint, most-shelved authors Your library is backed up privately and automatically — no account, no sign-up. Free for up to 100 books. Stacks Pro unlocks unlimited books, reading goals, 50 shelf scans a month and the Librarian: $2.99/month or $19.99/year with a 7-day free trial. Stacks is for people whose books are part of who they are. Catalog your shelves and see your library the way it deserves to be seen. — Terms of Use: https://zencodex.io/apps/stacks/terms Privacy Policy: https://zencodex.io/apps/stacks/privacy

Screenshots

PPAS eReader4 screens
Stacks4 screens

Verdict

The call

The clearest difference is in-app purchases: PPAS eReader at none against Stacks's 4. PPAS eReader also leads on iOS requirement (15.6 vs 17.0). Stacks's advantage is update cadence (every 6 days vs every 43 months). On price, 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. Stacks sells 4 in-app purchases, starting at $2.99 per month. PPAS eReader asks for nothing beyond the download.

UpkeepUpdate frequency

PPAS eReader ships an update every 43 months, Stacks every 6 days. The most recent releases landed on October 29, 2026 and October 25, 2026 respectively.

Scorecard3 real differences · 7 level
PPAS eReader versus Stacks: the parameters behind the verdict, then further details
ParameterPPAS eReaderStacks
PriceFreeFree
Rating—5.0 (1 ratings) — better
Positive reviews—100.0% of reviews
Number of ratings—1 — better
Update frequencyEvery 43 monthsEvery 6 days — better
AdsNoNo
In-app purchasesNo — betterYes
Monetization—Freemium
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.6 — better17.0
Further details — not scored
Size46 MB15 MB
Age rating4+4+
DeveloperXentral MethodsZenmonkeys Digital LLC

In-app purchases

None

PPAS eReader

No in-app purchases

4 purchases

Stacks

Subscriptions2
  • Pro Monthly$2.991 Month
  • Pro Yearly7 Days trial$19.991 Year
One-time2
  • 3 Scans$0.99
  • 15 Scans$3.99

Questions

Is PPAS eReader free?
PPAS eReader is free to download, with no in-app purchases.
Is Stacks free?
Stacks is free to download, with in-app purchases available.
Do PPAS eReader or Stacks have ads?
Neither PPAS eReader nor Stacks shows ads.
Which is updated more often, PPAS eReader or Stacks?
PPAS eReader ships an update every 43 months, and Stacks every 6 days. Most recently, PPAS eReader was updated on October 29, 2026 and Stacks on October 25, 2026.

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