Various "NewSpace" companies in India are trying to figure out how to move forward in the space sector, to provide India's version of SpaceX:
One such company is Bellatrix Aerospace, founded by some young college grads who have previously done work for ISRO on satellite propulsion.
Their business model is based on 2 proposed rocket designs, Chetak and Garuda, both of which would use engines running on liquid methane fuel and liquid oxygen, as well as simple battery-powered electric turbopumps.
Liquid methane, more commonly known as Liquefied Natural Gas (LNG) has the advantage of being the lightest, most efficient and cleanest-burning fuel that's still available as a cheap commodity, while also being relatively safe and easy to work with. This would be in contrast to ISRO's choice of cryogenic liquid hydrogen fuel for its rockets, which although being the highest-performance fuel, is much more expensive to handle and store, since its extremely low temperature requires special measures for safe handling and containment. Methane offers slightly less performance, but is largely free from these troubles. Companies like SpaceX have pursued the strategy of optimizing for cost rather than purely for performance, and Bellatrix seems to be taking a similar approach.
ISRO has more recently chosen to develop a semi-cryogenic engine burning kerosene and liquid oxygen, to lower the operating costs for its planned future reusable launch vehicles. But unlike kerosene, methane is a lighter, cleaner-burning fuel that does not suffer from problems of coking (charred residue), which can build up and eventually clog an engine that is being reused again and again. So again, Bellatrix's choice of fuel seems to offer some interesting advantages. Nobody has yet flown a methane-fueled rocket, however SpaceX and competitor Blue Origin are busy developing methane engines for their planned next-generation launch systems.
Bellatrix's choice of simple battery-powered electric turbo-pump based on brushless DC motor is meant to avoid the complexity of the plumbing required for traditional high-performance fuel-powered turbopumps, which are the most expensive and vital component of any rocket. The extra weight of that battery means a performance penalty, however using newer light-weight high-power lithium batteries means the penalty shouldn't be too bad for a smaller rocket. (I'll bet these guys probably figured that out while working on battery-powered electric satellite thrusters for ISRO.)
As per their website, Bellatrix plans to initially build and reusably operate Chetak, the smaller of the 2 launch vehicles, for delivering nanosatellites to orbit. This would allow them to shake down and iron out any kinks in their basic design engineering while doing this. Later on, they would seek to build and reusably operate the larger Garuda, which would have payload lift capacity similar to a Falcon-1 class rocket. The prices shown on their website are $2M for Chetak and $5.4M for Garuda, which for these type of payloads would be the cheapest by far of any launch operator anywhere.
The US govt, seeing the ability of India to potentially disrupt the lower end of its launch market, is now trying to push for special conditions in any Commercial Launch Services Agreement with India: