There are several problems with the samplephonebook UI:

• Menus should be used instead of buttons where applicable
• Filtering page should be simplified (three modes - search by name/phone/email)
• The default engine should be used when it starts up
• The contact editor page needs to be cleaned up - on wide displays, the label and text edit should be on the same line, the avatar button and image display should be separated
• Code should be tidied up in general