These days, equavalent salaries in india are between 1/4th to 1/2 of equavalent american or uk salary for the same job. Adjusting for cost of living is a bit tricky as there are many things which are cheaper in India, but many things that a sw developer may want to buy are not so. In general electronic items are a bit more expensive in India, but things like rent, cost of food, clothing, cost of a basic car are lesser here in India. OTOH, mostly it is not apples to apples comparison. e.g. you can get cars for 5-8000 usd here in India, but those cars would most likely be illegal to sell in the US. When the manufacturers sell the same exact model here in India, the prices are a lot higher.

So if OP says that they get 1/4th of the salary that people from US get for same role, then I feel that he is most likely underpaid.

>but those cars would most likely be illegal to sell in the US. When the manufacturers sell the same exact model here in India,

I'm curious what you mean by illegal. Do you mean they won't pass emissions or safety?

Mostly will not pass safety or minimum equipment standards. Renault was known to sell cars in India with airbags that were inferior to what they supplied elsewhere. Indian emission laws are fairly strict but based on euro standards, so most cars should pass non ca emissions test.

Hmm, thats interesting. I would have thought that it would be cheaper to mass produce just one version for all markets.

If they earn the equivalent of 30-50k (25% of a US senior IC), I imagine they can afford a decent standard of living, eg in Mumbai.

30k usd maps to 2.2million inr. Which is the kind of pay a quality junior employee with 3-4 years of experience can get in a quality firm. There has been an explosion in tech salaries in the last 4-5 years and these days most companies are finding it tough to fill up their positions. Quality resources can easily get 50% of what a equavalent role would get them in the US.

There's no such thing as a 'fair' rate.