---
title: "R21 - Reviews, Revenue and Downloads in United States | Apple App Store"
description: "R21 is a new six-level reading series carefully designed to help young learners develop the skills they’ll need to succeed in the 21st century. Each book covers a range of topics and makes use of the "
---

# R21 — United States

![R21 App Icon](https://is1-ssl.mzstatic.com/image/thumb/Purple116/v4/90/0c/58/900c58a7-f04b-84c2-136a-453ae29a2aca/AppIcon-0-0-1x_U007emarketing-0-7-0-85-220.png/434x0w.png)

**Developer:** [CAVES BOOKS](https://apptail.io/developer/caves-books-FDlb) (Taiwan)
**Category:** Education
**Rating:** N/A (0 ratings)
**Price:** Free
**Bundle ID:** tw.com.cavesbooks.r21
**Store:** Apple App Store
**Country:** United States
**Version:** 1.24 (released 2023-12-05)
**Original Release:** 2017-02-09

**App Store Link:** [Download on Apple App Store](https://apps.apple.com/us/app/app/id1197252445)
**AppTail Page:** [https://apptail.io/app/r21-pvtj/united-states](https://apptail.io/app/r21-pvtj/united-states)

## R21 Description
R21 is a new six-level reading series carefully designed to help young learners develop the skills they’ll need to succeed in the 21st century. Each book covers a range of topics and makes use of the latest Content and Language Integrated Learning (CLIL) methods to ensure they’ll appeal to young children and have a connection to children’s wider studies and experiences.
With R21, reading is fun, inspiring as well as informative, and children will not only develop their reading competence but also become a great thinker in the 21st century.

## R21 Screenshots
- [Screenshot 1](https://is1-ssl.mzstatic.com/image/thumb/Purple113/v4/b8/3d/32/b83d32ff-9487-ec1c-9ad8-fbb2c9d3f41c/pr_source.png/1242x2688.png)
- [Screenshot 2](https://is1-ssl.mzstatic.com/image/thumb/Purple113/v4/57/98/d3/5798d323-161f-da6e-13d7-0720fb4fc6a5/pr_source.png/1242x2688.png)
- [Screenshot 3](https://is1-ssl.mzstatic.com/image/thumb/Purple113/v4/f6/c3/68/f6c3682b-a344-2750-ed32-5b2e7fe2ceab/pr_source.png/1242x2688.png)





## R21 Discovered Keywords
- r21

## Apps Similar to R21
- [Spotlight - Englisch lernen](https://apptail.io/app/spotlight-englisch-lernen-Stl/united-states)
- [全英文看图背单词](https://apptail.io/app/app-Pxgc/united-states)
- [Bopomofo - pinyin to zhuyin](https://apptail.io/app/bopomofo-pinyin-to-zhuyin-FhGc/united-states)
- [Chinese Track](https://apptail.io/app/chinese-track-JqKc/united-states)
- [MyCT My Chinese Tutor](https://apptail.io/app/myct-my-chinese-tutor-Qlhd/united-states)
- [Ponddy Chinese Dictionary](https://apptail.io/app/ponddy-chinese-dictionary-Vlhd/united-states)
- [Quran English Word by Word](https://apptail.io/app/quran-english-word-by-word-Cwje/united-states)
- [EZ Test - TOEIC® Writing](https://apptail.io/app/ez-test-toeic-writing-zFje/united-states)
- [saasguru: Sales force Training](https://apptail.io/app/saasguru-sales-force-training-wvtj/united-states)
- [English Talk, Chat with AI Bot](https://apptail.io/app/english-talk-chat-with-ai-bot-ncnm/united-states)

## R21 Available In
- [Taiwan](https://apptail.io/app/r21-pvtj/taiwan)
- [Hong Kong SAR China](https://apptail.io/app/r21-pvtj/hong-kong)
- [Brazil](https://apptail.io/app/r21-pvtj/brazil)
- [Belarus](https://apptail.io/app/r21-pvtj/belarus)
- [Canada](https://apptail.io/app/r21-pvtj/canada)
- [Chile](https://apptail.io/app/r21-pvtj/chile)
- [Colombia](https://apptail.io/app/r21-pvtj/colombia)
- [Germany](https://apptail.io/app/r21-pvtj/germany)
- [Spain](https://apptail.io/app/r21-pvtj/spain)
- [Finland](https://apptail.io/app/r21-pvtj/finland)
- [France](https://apptail.io/app/r21-pvtj/france)
- [United Kingdom](https://apptail.io/app/r21-pvtj/united-kingdom)
- [Ireland](https://apptail.io/app/r21-pvtj/ireland)
- [Italy](https://apptail.io/app/r21-pvtj/italy)
- [Japan](https://apptail.io/app/r21-pvtj/japan)
- [Mexico](https://apptail.io/app/r21-pvtj/mexico)
- [Nigeria](https://apptail.io/app/r21-pvtj/nigeria)
- [Norway](https://apptail.io/app/r21-pvtj/norway)
- [Peru](https://apptail.io/app/r21-pvtj/peru)
- [Poland](https://apptail.io/app/r21-pvtj/poland)
- [Portugal](https://apptail.io/app/r21-pvtj/portugal)
- [Sweden](https://apptail.io/app/r21-pvtj/sweden)
- [Singapore](https://apptail.io/app/r21-pvtj/singapore)
- [Türkiye](https://apptail.io/app/r21-pvtj/turkey)
- [United States](https://apptail.io/app/r21-pvtj/united-states)
- [Argentina](https://apptail.io/app/r21-pvtj/argentina)
- [South Africa](https://apptail.io/app/r21-pvtj/south-africa)
- [Austria](https://apptail.io/app/r21-pvtj/austria)

---

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