I fast 16:8 and I've cycled through several fasting apps over two years. What pushed me out each time wasn't a paywalled timer — most of the big ones do give you that free. It was the ads in a health app, and pricing that turns out to be quiz-dependent rather than fixed. One of the largest says on its own site that the price varies with what you choose during signup; another lists ten different price points across four tiers. So I built Halfday with one price and no quiz. The timer, the fastin...