Re: "reduce dependence on foreign systems while improving accuracy"
Yes it will be more accurate because the Indian Regional Navigational Satellite System (IRNSS) is a regional satellite navigation system and as such designed to reach into Valleys and Streets with tall buildings.
There will be two kinds of services:
1/ Special Positioning Service (SPS)
2/ Precision Service (PS)
This is compatible with GPS devices both services will be carried on L5 (1176.45 MHz) and S band (2492.028 MHz). The navigation signals are transmitted in the S-band frequency and broadcast through a phased array antenna to keep required coverage and signal strength.
The data structure for SPS and PS takes advantage of the fact that the number of satellites is reduced since its not covering the globe and broadcast ionospheric corrections for a grid of 80 points to provide service to single frequency users.
There is no reason why device manufacturers can not update the software to decode these messages if their devices are receiving L5 GPS signals.
iPhone 14 Pro and iPhone 14 Pro Max are the first iPhones to offer dual-frequency GPS they are being exceptionally lazy only doing L1C/A
while ZenFone 6, OnePlus Nord, Galaxy S20, Pixel 4 etc all do L5 today
L5 GPS is something I look for on phones, It makes a huge difference
either way good for India for making Navigation better in their region !