Comparison

IPA Phonetic Keyboard vs TwinPDFViewer

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

Head to head
About

IPA Phonetic Keyboard

This free keyboard provides easy access to all IPA and extended IPA symbols. Its intuitive layout mirrors the IPA chart, making symbol input fluid and efficient for linguists, language learners, and enthusiasts.

Highlights
  • Full IPA chart (2020) symbols
  • ExtIPA chart (2016) symbols
  • Organized symbol sections
  • Intuitive symbol layout
  • Convenient input for common characters
  • Completely free, no ads
Read full description

Behold the first completely FREE IPA keyboard on the App Store designed for linguists, language learners, and hobbyists. It is designed to be lightweight and fluid, matching up to the user experience of the system emoji keyboard. =FEATURES= - Includes ALL symbols on the newest standard IPA chart (2020 ver.) - Includes most symbols (the ones available in Unicode) on the newest standard extIPA chart (2016 ver.) - Symbols are divided into sections just like the IPA chart(-duh!): consonants, non-pulmonic, other symbols, vowels, suprasegmentals, tones and word accents, and diacritics - Symbols are arranged naturally, with a layout designed for you to find the symbols you want more quickly (especially the vowels, it's cleverly designed to match the layout on the IPA chart) - Convenient input for "[]", "//", "~", "◌", space, and return on the top of the keyboard - Completely free, NO ADS =EXTERNAL LINKS= For more information on IPA (International Phonetic Alphabet), refer to https://en.wikipedia.org/wiki/International_Phonetic_Alphabet The developer, Vince14Genius's GitHub: https://www.github.com/Vince14Genius/

About

TwinPDFViewer

Features
Read full description

2つのPDFファイルを事前に選択し、中央タップで瞬時に切り替えて表示できるPDFビューアアプリです。文書の比較や検討に最適な機能を搭載しています。 主な機能 ◆デュアルPDF切り替え ・Front PDFとBack PDFを事前に選択・登録 ・中央タップで瞬時にPDFを切り替え ・デバイス内のファイルまたはフォルダから選択可能 ◆直感的な操作 ・スワイプでページ送り ・ピンチでズーム操作 ・タップでコントロール表示/非表示 ◆柔軟な表示モード ・単ページ表示 ・見開き表示(奇数・偶数ページ対応) ◆章移動機能 ・フォルダ内のPDFファイル間をChapterとして移動 ・前の章・次の章への簡単なナビゲーション <用途例> ・文書の比較・検討 ・資料の照合・確認 ・学習用教材の並行表示 ・契約書や仕様書の比較 ・翻訳作業での原文・訳文の切り替え確認 TwinPDFViewerは、2つのPDF文書を効率的に比較・検討したいすべてのユーザーに最適なソリューションです。ビジネス文書の比較から学習用途まで、様々なシーンで活用できるPDFビューアをお試しください。

Screenshots

IPA Phonetic Keyboard4 screens
TwinPDFViewer1 screens

Verdict

The call

The clearest difference is in-app purchases: TwinPDFViewer at none against IPA Phonetic Keyboard's 3. IPA Phonetic Keyboard's advantage is update cadence (every 4 months vs every 14 months) and iOS requirement (14.0 vs 18.2). 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. IPA Phonetic Keyboard sells 3 one-off in-app purchases. TwinPDFViewer asks for nothing beyond the download.

UpkeepUpdate frequency

IPA Phonetic Keyboard ships an update every 4 months, TwinPDFViewer every 14 months. The most recent releases landed on November 2, 2026 and October 30, 2026 respectively.

Scorecard3 real differences · 7 level
IPA Phonetic Keyboard versus TwinPDFViewer: the parameters behind the verdict, then further details
ParameterIPA Phonetic KeyboardTwinPDFViewer
PriceFreeFree
Rating4.5 (193 ratings) — better—
Positive reviews92.1% of reviews—
Number of ratings193 — better—
Update frequencyEvery 4 months — betterEvery 14 months
AdsNoNo
In-app purchasesYesNo — better
MonetizationFree—
DevicesiPhone, iPad, iPod — betteriPhone, iPad
Requires iOS14.0 — better18.2
Further details — not scored
Size2 MB10 MB
Age rating4+4+
DeveloperVincent CaiDaichi Hayashi

Bugs and requests

IPA Phonetic Keyboard

Reported bugs

2 issues
  • Vowel [ʁ] displays incorrectly
  • Keyboard disappears after switching, requiring settings access to re-enable

Requested features

4 requests
  • Add angle brackets and parentheses for orthographic notation
  • Implement a 'frequently used' section for common symbols
  • Allow users to rearrange the keyboard layout
  • Add support for laryngeal notation in Proto-Indo-European

TwinPDFViewer

Not enough reviews yet to summarise bugs or requests.

In-app purchases

3 purchases

IPA Phonetic Keyboard

One-time3
  • Donation: Buy me a drink$2.99
  • Obsolete/Non-Standard Symbols$5.99
  • Donation: Buy me a meal$9.99
None

TwinPDFViewer

No in-app purchases

Questions

Is IPA Phonetic Keyboard free?
IPA Phonetic Keyboard is free to download, with in-app purchases available.
Is TwinPDFViewer free?
TwinPDFViewer is free to download, with no in-app purchases.
Do IPA Phonetic Keyboard or TwinPDFViewer have ads?
Neither IPA Phonetic Keyboard nor TwinPDFViewer shows ads.
Which is updated more often, IPA Phonetic Keyboard or TwinPDFViewer?
IPA Phonetic Keyboard ships an update every 4 months, and TwinPDFViewer every 14 months. Most recently, IPA Phonetic Keyboard was updated on November 2, 2026 and TwinPDFViewer on October 30, 2026.

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