Comparison

Readwise vs Build

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

Head to head
About

Readwise

This app helps you retain more of what you read by centralizing and revisiting your highlights from various reading platforms. It uses spaced repetition and active recall techniques to improve memory and offers features like tagging, note-taking, and OCR for physical books.

Highlights
  • Synchronize highlights from multiple platforms
  • Daily review habit via app and email
  • Spaced repetition and active recall
  • Tag, note, and search highlights
  • OCR for paper book highlights
  • Convert highlights to flashcards
Features
Read full description

Readwise helps you get the most out of what you read by making it fun & easy to revisit your highlights from all your favorite reading platforms in one place. Quickly synchronize your highlights from Kindle, Apple Books, Instapaper, Pocket, Medium, Goodreads, and even paper books. Then start building a daily review habit using the app and daily email. By reviewing your highlights every day, you'll retain dramatically more and you'll finally stop forgetting all the details from books you just finished! --- “Readwise is my favorite new service this year. Save highlights from Kindle, Instapaper, and now tweets... one of the best long-term personal learning tools I’ve come across.” — Caleb Hicks “Besides my Kindle, Readwise has been the most influential tech for improving my reading process.” — Blake Reichmann “If you use Kindle or Instapaper or just enjoy keeping and reading highlights, please sign up to Readwise. It will become one of your cherished services.” — Christopher Galtenberg --- ACTUALLY USE YOUR HIGHLIGHTS Highlighting is great, but why bother if you're never going to see any of your highlights again? Readwise makes it easy to quickly liberate all your highlights into one place, ensuring that you'll actually see and use them, including highlights from: • Amazon Kindle • Apple iBooks • Instapaper • Pocket • Medium • Goodreads • Twitter • Physical Books (using OCR) • Manual Input • CSV Upload STOP FORGETTING WHAT YOU READ How often do you finish a book, only to forget the key ideas two weeks later? We don't remember things by just reading them once. Readwise solves this problem using scientifically proven learning techniques called Spaced Repetition and Active Recall. Readwise resurfaces the right highlights at the right times using a daily email and an app. Readwise even makes it possible to convert your best highlights into flashcards for added retention. TAG, NOTE, SEARCH, AND ORGANIZE With your highlights all in one place, Readwise enables you to organize and connect these ideas in new ways. Use search to find a highlight instantly; use tag to organize highlights within your library; use notes to add your own annotations. HIGHLIGHT PAPER BOOKS Readwise also makes it possible to take highlights from your physical books and papers using your phone’s camera. Just snap a pic, highlight with your finger, and have your favorite highlights saved forever. --- If you are not already a Readwise subscriber, you can get started immediately with a 30-day free trial with no credit card upfront. At the end of the trial, you will not be charged unless you choose to subscribe to Readwise Full or Readwise Lite. Price may vary by location. Manage your subscription from your dashboard. --- Support: Check out readwise.io/faq or email us at hello@readwise.io Privacy Policy: https://readwise.io/tos Terms of Service: https://readwise.io/privacy

About

Build

This app offers short, focused math drills for addition, subtraction, multiplication, and division. It provides instant feedback and tracks progress through engaging sessions designed for quick practice.

Highlights
  • Short, focused math practice sessions
  • Master addition, subtraction, multiplication, division
  • Instant feedback with haptics, color, and sound
  • Smart question rotation for confidence
  • Progress tracking and summaries
  • Works offline, no ads, no accounts
Features
Read full description

Turn 1–5 minutes into real math practice. Build‑A‑Math is a focused drill app for mastering addition, subtraction, multiplication, and division. Tap answers on the large on‑screen keypad, get instant feedback, and watch your progress bar fill as you work. # Why it works - Short, focused sessions (1–5 minutes) keep practice consistent and stress‑free. - Instant feedback with gentle haptics, color, and sound—celebrate correct answers and learn from mistakes. - Smart rotation of questions: a small set of problems stays in play; fast, correct solves are retired so you can move forward confidently. - Results you can feel: a cheerful summary shows Questions tried and Mastered today after each session. # Designed for real life - Pick the operations you want: +, −, ×, ÷. - Auto‑check answers as you type (single‑digit checks instantly; two‑digit checks on the second digit). - Works great in portrait or landscape on iPhone and iPad. - No ads. No accounts. Works offline. Perfect for classroom warm‑ups, brain breaks, and at‑home practice—anytime you have a minute (or five).

Screenshots

Readwise4 screens
Build2 screens

Verdict

The call

The clearest difference is in-app purchases: Build at none against Readwise's 8. Readwise's advantage is ratings volume (1.5K vs 3) and iOS requirement (15.5 vs 17.6). On price, rating, update cadence and ads 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. Readwise sells 8 in-app purchases, starting at $4.99 per month. Build asks for nothing beyond the download.

ReceptionRating · Positive reviews · Number of ratings

On the App Store both sit at effectively the same score — 4.8 for Readwise against 4.7 for Build. That said, the two scores are not equally well evidenced: Readwise has 1.5K ratings behind it against 3, so its average is the more settled of the two.

UpkeepUpdate frequency

Readwise ships an update every 2 weeks, Build fortnightly. The most recent releases landed on September 24, 2026 and June 1, 2026 respectively.

Scorecard4 real differences · 6 level
Readwise versus Build: the parameters behind the verdict, then further details
ParameterReadwiseBuild
PriceFreeFree
Rating4.8 (1.5K ratings) — better4.7 (3 ratings)
Positive reviews72.2% of reviews—
Number of ratings1.5K — better3
Update frequencyEvery 2 weeksFortnightly — better
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree with in-app purchasesFree — better
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS15.5 — better17.6
Further details — not scored
Size110 MB1 MB
Age rating12+4+
DeveloperReadwise, IncWeiran Ye

Customer experience

Readwise

All ratings1,513 ratings
Positive95.7%
Neutral1.5%
Negative2.8%
Written reviews324 reviews
Positive72.2%
Neutral7.7%
Negative20.1%

Build

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Bugs and requests

Readwise

Reported bugs

3 issues
  • Frequent app crashes
  • Sync failures with certain accounts
  • Unreliable highlight capture

Requested features

5 requests
  • Add support for more reading apps
  • Improve sync and import capabilities
  • Introduce more customization options
  • Enhance search and organization tools
  • Develop a more intuitive mobile interface

Build

Not enough reviews yet to summarise bugs or requests.

In-app purchases

8 purchases

Readwise

Subscriptions8
  • Readwise Lite Monthly$4.991 Month
  • Readwise Lite Monthly$6.991 Month
  • Readwise Full Monthly Plan$8.991 Month
Show 5 more
  • Readwise Full Monthly$12.991 Month
  • Readwise Lite Yearly$52.991 Year
  • Readwise Lite Yearly$66.991 Year
  • Readwise Full Yearly$94.991 Year
  • Readwise Full Yearly$119.991 Year
None

Build

No in-app purchases

Questions

Is Readwise free?
Readwise is free to download, with in-app purchases available.
Is Build free?
Build is free to download, with no in-app purchases.
Which has better reviews, Readwise or Build?
Readwise is rated higher. Readwise averages 4.8 out of 5 from 1.5K ratings, while Build averages 4.7 from 3 ratings.
Do Readwise or Build have ads?
Neither Readwise nor Build shows ads.
Which is updated more often, Readwise or Build?
Readwise ships an update every 2 weeks, and Build fortnightly. Most recently, Readwise was updated on September 24, 2026 and Build on June 1, 2026.

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