Hello. I could be wrong, but it seemed to me that different services offer different prices from $8 to $13 per year. However, it's worth noting that the price may vary depending on the plan that you choose. When you're choosing a domain, the industry in which your business develops also plays a huge role. My business suits .app because my business is related to IT, more specifically software development and this domain suits us best. We got our domain due to https://www.namecheap.com/domains/registration/gtld/app/ . The way I see it, it's the domain that allows us to stand out from the competition. If you have any questions, text me, please.