The Mozhi is a popular romanization[1] scheme for Malayalam script.
[2] It is primarily used for Input Method Editors for Malayalam and loosely based on ITrans scheme for Devanagari.
This system does not need the use of diacritics; instead, uses letter case distinction to indicate difference in vowel lengths and different groups of consonants.
However, Mozhi has additional mappings to allow input using only the lowercase letters.
Since Mozhi is targeted for input, it has features tuned for that:[1]