That system is going to require a lot of complex math — fortunately, the help desk will be a local call. The US GPS system requires math that makes advanced calculus look like a sunday school picnic. Fortunately for users, the GPS receiver has the solutions built in and are not difficult to use.
Anyone can use the automotive ones, the hunting ones are more difficult, but not beyond the capabilities of any high school graduate.
I was thinking about the systems level — where you even need to incorporate special relativity. Then, it seemed to me that mixing Geo-stationary and NEO satellites together would make it even more complex. There are a lot of scary-smart engineers in India; so I have little doubt they'll pull it off (despite my cheap shot about call center help desks, which seem to be located mostly in India).