Is there an app that I can read the novel on?

it's in korean, but the raws are on this site, or were you looking for a manga app?

https://toonkor.shop/악녀는-모래시계를-되돌린다

You can read on the app called webnovel

idk if theres an app for the novel but here's the link to a website that has it! https://boxnovel.com/novel/the-villainess-turns-the-hourglass/chapter-1