OK, so maybe it is because my group and I are all relatively tech illiterate but I, as the DM, am trying to share characters I created in a campaign to my players. If they sign into the link on their phone the link directs them to either chose one of the characters I created or to create their own. So far so good.  If they try to sign into the link on their iPad it just signs them into their dnd account with no option to choose on of my characters or access any of the sourcebooks I own on my master level account.  Am I missing something or do players have to use the shareable link on their phone.  

Make sure they are logged in before using the join link and see if it behaves properly then.

Are you trying to share a created character with the party so that they can play them in a campaign with you?

In that case, you should do the following:

• Create a campaign if you haven't already
• For each character:
  • Follow the invite link into your own campaign
  • Select the character
  • at the bottom click "Join with this character"
  • go back to the campaign view and click "Unassign"
• Each player should follow the invite link in and claim the appropriate character

If you are just sending the Share link from the character sheet, all it does it let you view the character.