CC has a 'Read' button, making that operation simple (assume you have set CC up to work with the appropriate reader app)
Since the user will not have easy WiFi network access: 'Wispersync' (or a cell data plan) is a good choice as long as there is the proper 'cellular service' available at her location so she can get library books.
IMHO Avoid 'touch required' (or can't be disabled. Think of those PC assistive features you have vailable on your desktop) devices.
Older hands are not always steady.
Learning (and making) those complex gestures will frustrate (and make them use another, older one
)
And don't totally discount the use of 'New tech'. My 90+ aunt Skypes me occasionally from her room at the Senior facility.