Polytonic Greek. Archaic local variants, all breathing marks.

1. All ten classical marks.

   Smooth and rough breathings, acute, grave, and circumflex accents, iota subscript, diaeresis, macron, breve, and the philologist's underdot. Combine them freely. Mutually exclusive marks, like acute and grave, or macron and breve, never fight each other.

2. Two ways to type.

   Enter a vowel first and decorate it with one tap, or queue up the diacritics you want and apply them all to the next vowel. Whichever mental model you prefer, Tonos follows along.

3. Three layers, one keyboard.

   Letters uses the common Greek keyboard ;ςΕΡΤΥ layout. Numbers holds digits and punctuation, including ano teleia. Archaic holds rare letters from languages that use the Greek alphabet:

   • digamma (ϝ)
   • stigma (ϛ)
   • archaic koppa (ϙ)
   • koppa (ϟ)
   • sampi (ϡ)
   • san (ϻ)
   • heta (ͱ)
   • yot (ϳ)
   • sho (ϸ)
   • kai ligature (ϗ)
   • Pamphylian digamma (ͷ)

   Plus cursive and lunate letterforms, which are variant glyphs of standard Greek letters used in manuscripts and papyrology: β (ϐ), θ (ϑ), π (ϖ), κ (ϰ), ρ (ϱ), σ (ϲ), Θ (ϴ), ε (ϵ), along with reversed or dotted forms ϶, ͻ, ͼ, ͽ.

4. NFC Unicode output.

   Canonically precomposed where Unicode provides a precomposed form. Characters like ἄ, ᾄ, ῶ, and ῷ drop cleanly into any app, document, or database. No legacy codepoints, no lookup tables, no surprises for your downstream tools.

Tonos Pro is an optional one-time upgrade that unlocks two features for polytonic Greek. Both run entirely on the device, with no network access and without the Full Access keyboard permission.

1. Spell check.

   Up to three correction candidates appear above the keyboard when the word you have typed is not attested. The dictionary is a Hunspell-compressed inventory of polytonic forms drawn from Classical, Koine, and Byzantine corpora. The keyboard memory-maps the dictionary, so it adds only a few megabytes of resident memory.

2. Typeahead.

   After you finish a word, Tonos proposes up to three likely continuations from an on-device trigram language model trained on roughly thirty million polytonic tokens: the GLAUx and Diorisis Ancient Greek corpora, a 19th-century Katharevousa slice from Greek Wikisource, and the Byzantine vernacular corpus. Tap a suggestion to insert it. Breathings, accents, and iota subscript are preserved exactly as the model saw them.

Pro is a single non-consumable purchase. One price, one tap, restores across any device signed in to your Apple ID. The free keyboard remains complete on its own.