You can send bitcoin to any Bitstack user or another Bitcoin compatible wallet for free with Bitstack.
To send bitcoin to any Bitstack user:
Tap on the ⬆️⬇️ button in the app
Enter at least €0.01 or 1 sat (0.00000001 BTC) and tap Send
Find your recipient's name, current phone number, or email address
Tap Continue to verify your transaction details
Tap Confirm
To send bitcoin using the blockchain:
Tap the Wallet tab in the app
Tap the Send button
Enter the amount of bitcoin you want to send
Scan a QR code or tap Send to enter the recipient's BTC address
Tap Continue
Select a speed
Tap Confirm
To receive bitcoin from another wallet:
Tap the Wallet tab
Tap the Receive tile
Scan the QR code or copy the Bitcoin address