When you have a textbox that you wish to allow the User to enter values into; do so in an intuitive and nice way. Keyboard presses on a phone should in general be avoided as much as possible, hence when ever you are forced to display a keyboard – show the right keyboard as the first option! Your users will definitely love you for it!
On a WP7 phone, 2 keyboards are possible. The default (left) and the numeric (right):
Update: More than 2 exists! I've so far counted 8!
So - how does one force the numeric keyboard? Here comes in the InputScope attribute to the rescue.
In XAML (verbose version) it looks like this:
And the non-verbose XAML version looks like this:
<TextBox Height="72" HorizontalAlignment="Left" Margin="186,46,0,0" x:Name="tbxPrice" VerticalAlignment="Top" Width="244" InputScope="CurrencyAmount"/>
It will make the Numeric keyboard pop up when ever the textbox is entered.
Details can be found here: http://msdn.microsoft.com/en-us/library/ff626520(VS.92).aspx
Another (better) info is found here: http://msdn.microsoft.com/en-us/library/system.windows.input.inputscopenamevalue%28VS.96%29.aspx