The keyboard mirrors Tamil phonology: consonant variants (pure consonants, consonant+u, consonant+a) and medial vowels follow predictable, phonetically logical groupings. Dead-keys and toggle modes are used sparingly—only where necessary for archaic letters or special punctuation—so modern users aren’t burdened by legacy complexity. For users of mobile devices, the layout adapts to long-press popups for extended characters, maintaining the same phonetic grouping to minimize re-learning.