Could you make it a web app? I don't want to install apps on my phone for security/privacy reasons.
Since your domain has an extra (and a little hard-to-see) Z in it, you have to find some way to make people very aware of that. Perhaps you could make your logo that makes the middle z capitalized and in a contrasting color (I had to do italics here instead):
sizzzle.app vs sizZzle.app vs sizZzle.app
Or just pick a different name if you're not already all-in on this one, especially since it's not a .com.. for example, zizzle.app seems to be available, but always check USPTO's TESS to make sure you're not stepping on a federally registered trademark, too.
Here was a quickie logo I made using https://www.adobe.com/express/create/logo: https://www.imgpaste.net/image/KvJX64