Multiple wallets

You can create multiple wallets with p2pkh & p2wpkh adressess.

Transactions

You can send and received test bitcoins.
You can also use additional features like storing data in chain with OP_RETURN.

Testnet3

You can interact with real bitcoin testnet which imitates main chain.
Use it for developing or learning.

Open source

Wallet is written with expo and bitcoin-js.
Source code can be found HERE.