There are many third-party wallets available across desktop, mobile, and hardware. Many of which allow for instant account creation. You can find all of the known HBAR-supported wallets, here: https://www.hedera.com/wallets 

For specific help on creating a Hedera account using a third-party wallet, please see the official "Wallets" FAQ section: https://help.hedera.com/hc/en-us/categories/360000099958