In the text Dialect Accent Features for Establishing Speaker Identity, Manisha Kulshreshtha and Ramkumar Mathur write, "A few sounds, borrowed from the other languages like Persian and Arabic, are written with a dot (bindu or nuqtā).
Devanagari also includes coverage for the Dravidian consonants ऴ, ḻa /ɻ/; ऱ, ṟa /r/ and ऩ, ṉa /n/.
The Bengali-Assamese script has ড় ঢ় য়, which are variations of ড ঢ য; however, ব and র are completely different in nature.
[4] There are two use cases found for it: Sindhi's and Saraiki's implosives are accommodated in Devanagari with a line attached below—a diacritical bar: ॻ [ɠə], ॼ [ʄə], ॾ [ɗə], ॿ [ɓə].
In Tamil script, the special character ஃ (ஆய்த எழுத்து, āyda eḻuttu) is used like nuqta to represent non-native consonants.