you can track wallets and more in testnet.tonscan.org

• https://testnet.dton.io/ - My first choice. GraphQL based, update with instantly without need refresh the page.
• https://testnet.ton.cx/ - shows full of important informations, more specifically, it shows the NFT Index ID, helps me a lot in many cases.
• https://testnet.tonscan.org/ - Obviously, the standard classic explorer UI. Very reliable as well.
• https://test-explorer.toncoin.org/ - High-skill usage explorer. I am not expert at TVM at this moment, but it looks cool.
• https://testnet.tonapi.io/ - High performance explorer with familiar API infra.

Explorer

• tonscan.org
• tonapi.io
• ton.sh
• ton.cx
• dton.io