tiktok app won't download from the app store

Is it stuck on waiting, or does the Get button not do anything at all? If it's a kid's phone or you've ever set up Screen Time, check Content & Privacy Restrictions, an app age limit will quietly block it. Otherwise it's usually storage (it needs a fair bit free to install, not just the download size) or a payment method problem on your Apple ID, even though the app is free. Signing out of Media & Purchases and back in clears a lot of stuck downloads too.