If I own Wayfinder's Guide to Eberron, will I get this book as well?
No. They are two separate books, and purchase of one does not automatically unlock both.
What happens to the content I already own?
You will keep your purchased content. If something is updated in ERFtLW, it will receive an update in WGtE. If something is not included in the new book, you will be able to continue using it on current characters, but will not be able to use it for new characters.
Will ERFtLW be available on the app?
Not at release. Because we have to make changes to live content, it will take us a little bit of time to get everything updated on the app.
Why aren't the Dragonmarked subraces adding spells to my spell list?
There will be some limited functionality on the character sheet at release. Dragonmarked subraces that add spells to a character will not automatically add the spells to the spell list, and will only be present on the character sheet in text form. This is something we plan on correcting in the future.
Where can I report bugs or issues with the book?
You can post your bugs or feedback in the (thread here)
As always, you can contact Customer Support.