iPad electronic health record vendor drchrono has officially made it past "startup" status. The company just netted another $2.8 million in funding from Internet investor Yuri Milner, more than four times the initial $650,000 Milner provided last summer. Add all that to the $675,000 the company earned in seed funding last fall, and that puts drchrono squarely in the $4 million-plus club. Along with the funding announcement, the company also launched its new billing module, which it says allows physicians to do create and submit bills and receive payments on their iPhones, iPads and other tablets. Announcement