With Burner Wallet, you can easily create a QR / link which includes a specific amount and an attached message. This works well for vendors offering specific price point items in a conference / event specific setting, or requesting any specified amounts of xDai from other xDai users.
1) Click Request.
2) Enter Requested Amount and any Message (or item if selling multiple items). Click Request.
3) A QR code is generated. This can be scanned directly, or the link can be copied and sent in any way you'd like (email, text, telegram etc). The link can be used any number of times by any user.
4) The link can be opened by another user. This auto-populates To Address, Send Amount, and Message. Click Send to process (user must have more than the requested amount of xDai in their wallet to process successfully).