Goal

A literary zonal auxlang for Indians and the Indian diaspora, to engage in intellectual writing / discourse / podcasts using native vocabulary without having to deal with the extreme inflectional learning curve that applied to India’s traditional literary / technical lingua franca (Sanskrit).

Approach

Use Sanskrit vocabulary but with a regularized and simplified grammar structure based on modern day Indo-Aryan and Dravidian languages. In this way, we build a lingua franca that resembles modern day Sanskritized literary registers of most Indian languages while remaining neutral and easy to acquire for anyone familiar with Sanskritized vocabulary.

Sample text

The Christian Lord’s Prayer as an example:

Svarga madhye asma sya pitā
Tva sya nāma sadā pavitra astu

Tva sya rājya āgamana kartu
Yathā svarga madhye tathā pṛthvī upari tva sya icchā pūrṇa bhutu

Adya asma artha dina sya bhojana dāna kartu
Yathā vayam asma sya śatru jana kṣamā karti tathā asma sya duṣṭa kārya kṣamā kartu

Vayām andhakāra madhye gamana kāraṇa na kartu, evam duṣṭa taḥ vayām rakṣā kartu
Tathāstu

Writing and phonology

IAST is used in this document. However, Navabhāṣā need not have a preferred writing script and should be written in any script that can fully represent Sanskrit phonemes, such as Devanāgarī, IAST, Tamil+Grantha. etc. Webpages and apps are encouraged to use an auto-transliteration feature such as Aksharamukha to allow users to view it in their preferred script, while printed materials should be made available in regionally legible scripts.

Spelling should be based on the Sanskrit etymology, but pronunciation need not follow Sanskrit prescription. Allowable regional pronunciation practices include omitting word-final schwa in some or all contexts or pronouncing it as a short open vowel, merging ṣ into ś, and  pronouncing r̩ as ri or ru.

Word order

Modern Indian languages have converged on a surprisingly consistent word order, and we use the same.
The basic word order SOV.
More precisely including adverbs and and postpositional phrases the order is: Subject + Time + Place + Manner + Indirect Object + Direct Object + Verb
Noun phrase order is Possessive/Demonstrative + Number/Quantifier + Adjective + Noun + Plural

Postpositions

Genitive: sya
Dative: artha
Sociative: saha
Thematic (About/Via/Without): viṣaye / mārga / vinā 
Instrumental: dvārā
Ablative (Origin vs. Comp.) taḥ / apekṣā 
Temporal (Before/After) pūrva / anantara 
Directional / Boundary prati / paryanta
Locative (In/On) madhye / upari 
Spatial (Inside/Outside) antara / bāhya 
Spatial (Above/Below) ūrdhva / tala 
Spatial (Behind/Front) pṛṣṭhe / sammukhe 
Spatial (Near/Far/Around) samīpa / dūra / parita

Pronouns / demonstratives

Not declined for gender
Person number: Nominal / Accusative / Stem for postposition
1st Sing: Aham / Mām / Ma
1st Plural: Vayam / Asmām / Asma
2nd Sing: Tvam / Tvām / Tva
2nd Plural:  Yūyam / Yuṣmām / Yuṣma
3rd Sing:  Tat / Tām / Ta
3rd Plural: Te / Tem / Te
3rd Reflexive: Sva / Svām / Sva
3rd Demonstrative: Idam / Idām / Ida

Nouns

Not declined except for optional plural marker (-jana for animate, -caya for inanimate)

Verbs

When borrowing verbs from Sanskrit (or from other languages like English), modern Indian languages exclusively borrow them as verbal nouns and pair them with auxiliary verbs. We universalize this practice to all verbs, except for a small set of auxiliary verbs.
Roots: Kar- (Active), As- (Static), Bhu- (Dynamic), Kāra- (Causative), Sthā- (Continuous). Suffixes: -ti (Present), -īt (Past), -iṣya 
(Future), -tu (Imperative), -tva (Completive).

Clausal words

Correlatives and interrogatives have parallel “as” / “so” / “?” words, and inflect like the pronouns (-m added for accusative, with Katham becoming Kathām and Kim staying the same, and the rest being inflected by postpositions).
Person / entity: Ya / Tat / Ka (animate) / Kim (inanimate)
Time: Yadā / Tadā / Kadā 
Place: Yatra / Tatra / Kutra
Manner: Yathā / Tathā / Katham
Quantity: Yati / Tati / Kati
If / then / yes vs. no: Yadi / Tarhi / Kim (at end of question)

Clausal links:
And: Evam
Or: Athavā
But: Kintu
Because: Kāraṇa 
Therefore: Ataḥ
Also: Api (at the end of the additional clause)
I.e.: Arthāt
Otherwise: Anyathā
Finally: Antataḥ

Numbers and measurements

Regularized using 1-9 numbers times the ten power. Ten power is defined using the “lakh crore” terminology rather than ancient names, to maximize recognizability and avoid ambiguity since different languages use different values for the same names.
1: Eka, 2: Dvi, 3: Tri, 4: Catur, 5: Pañca, 6: Ṣaṣ, 7: Sapta, 8: Aṣṭa, 9: Nava, 10: Daśa
100: Śata, 1000: Sahasra, 10k: Das Sahasra, 100k: Lakṣa, 1m: Das Lakṣa, 10m: Kōṭi, 100m: Das Kōṭi, 1b: Śata Kōṭi, 10b: Sahasra Kōṭi, 100b: Das Sahasra Kōṭi, 1t: Lakṣa Kōṭi, 10t: Das Lakṣa Kōṭi, 100t: Kōṭi Kōṭi

Measurement units use their international names to avoid ambiguity. The exception is units of time which use their Sanskrit names from year down to day, as well as “Vādana” for “hour”.