We can't provide a comprehensive comparison of Tata Bolt and Hyundai Grand i10 as the Tata Bolt has still been launched. The only reference we can give you that Tata Bolt has the first in class 5-inch touch screen infotainment system powered by Harman audio system and turbocharged Revotron petrol engine.
That's great if you are planning for a new car. It might interest you to know that Hyundai is planning to launch the facelift version of the Grand i10 sometime this year around August/September. The Grand i10 facelift is also likely to get AMT (Automated Manual Transmission). So if you are planning in 1-2 months, we suggest you to wait for its new facelift version and other new upcoming cars.