Adds context from paragraph 4

BEIJING, April 25 (Reuters) - BYD's 1211.HK 002594.SZ first-quarter profit leapt 100.4% from a year earlier, the fastest pace in nearly two years, as the Chinese electric vehicle giant extends its lead in its competitive home market after launching a smart EV price war.

Net profit totalled 9.2 billion yuan ($1.26 billion), a stock filing showed on Friday, compared with the company's earlier estimate of 8.5 billion yuan to 10 billion yuan.

Revenue came in at 170.4 billion yuan in the quarter, up 36.4% year-on-year versus a 52.7% rise in the previous quarter.

China's biggest EV maker has roiled the market over the past few months by offering its "God's Eye" driver-assistance system as a standard feature at no extra cost across its lineup, and unveiling a new super-charging EV technology platform.

Its step up in competition has prompted rivals including Leapmotor 9863.HK, Geely 0175.HK and Toyota 7203.T to follow suit with affordable EVs containing smart features.

By opening a new front in a years-long price war in the world's largest auto market, BYD is seeking to extend its lead in its home market, where it accounted for 13.6% of sales in January-March, up from 12.1% during the same period last year.

By contrast, Volkswagen VOWG.DE's two joint ventures in China saw their combined market share fall to 12.1% in the first quarter from 13.7% a year earlier.

At this week's Shanghai auto show, however, BYD and other automakers are avoiding boasts about advanced driving assistance capabilities and instead highlighting safety.

The hype around smart driving has been dampened by a government crackdown on marketing claims using terms such as "smart" or "autonomous" to describe the technology after a fatal crash of a Xiaomi SU7 at the end of March.

Outside of its home market, which makes up about 90% of BYD's total sales, the company is targetting exports of 800,000 vehicles this year.

BYD is also overhauling its European operations after strategic stumbles, Reuters has reported.

($1 = 7.2868 Chinese yuan renminbi)

(Reporting by Qiaoyi Li, Zhang Yan, Ethan Wang and Brenda Goh. Editing by Mark Potter)

((Ethan.Wang@thomsonreuters.com;))