Austin, Texas-based M.io, a Y Combinator-backed startup that is developing a universal messaging network, announced it has raised $5.75 million in funding led by previous investors Goldcrest Capital, Eniac Ventures and Two Sigma Ventures. The company was founded by Tom Hadfield and James Cundle in 2016. M.io has now raised $8.25 million from investors, including Goldcrest, Eniac, Two Sigma, Khosla Ventures, Y Combinator and Capital Factory.