The Unicode Character Viewer is actually an iPhone app, not an iPad app, but it will work on your iPad and will allow you to select the extra characters in the Samantha font in the Cricut Design Space app.
The video below shows the two apps you need for this and how they are used.
Some people have written me to say that they have had trouble finding the Unicode Character Viewer — you can download it from HERE.
The AnyFont app mentioned in my video is available HERE.
Note that you can still get the Samantha font on sale from Mighty Deals. Just type Samantha in the search field on their site.