Windows Phone has an on-screen keyboard. We call it the SIP (Software Input Panel). It appears when users give focus to a TextBox. The configuration of SIP keys varies by how the developer sets up the TextBox’s InputScope property.
On the far left is the DIGIT configuration. Remember, SIP configuration is meant to be an aid to the user, not a validation tool. Users can still use a physical keyboard to type in alpha characters, or use the clipboard to paste. Even with DIGIT, letters are possible.
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