STOCKHOLM, Jan 11 (Reuters) - Estonian startup Bolt said on Tuesday it had raised 628 million euros ($711.40 million) from investors led by Sequoia Capital and Fidelity Management and Research Co, taking its valuation to 7.4 billion euros ($8.38 billion). Bolt, a rival of Uber"s (UBER.N) ride-sharing and food delivery business, last raised funding in August at a valuation of more than 4 billion euros. The company also offers electric scooter rentals, car-sharing and a 15-minute grocery delivery service, catering to over 100 million customers in 45 countries and over 400 cities across Europe and Africa. "We are expanding all the five product lines extremely quickly, developing product R&D and rolling out in new cities," Chief Executive Markus Villig told Reuters in an interview. While Uber is the biggest rival for ride-hailing, Bolt faces competitors in food delivery including Just Eat Takeaway.com (TKWY.AS) and DoorDash (DASH.N), which entered Europe via a $8 billion purchase of Wolt. To gain customers, platforms often offer discounts leading to price wars in some markets. "In many cases we have been the driving force that actually lowers prices for consumers, so from day one, we were really focused on being frugal," Villig said. "We have been offering substantially lower prices than anybody else in the industry ... we expect this to continue." ($1 = 0.8828 euros)