## Metadata - Author: [[Daniel Doyon]] - Full Title: Reader: Frequently Asked Questions - Category: #articles - Summary: Changelog October 27, 2023 Updated instructions for adding document notes to include mobile and browser extension Updated mobile directions for customizing appearance Pro Tip: Use Ghostreader One of the coolest features of Reader is an AI reading assistant called Ghostreader (based on GPT-3). Ghostreader enables you to define terms, look - URL: https://blog.readwise.io/p/f8c0f71c-fe5f-4025-af57-f9f65c53fed7/ ## Highlights - Pro Tip: Use Ghostreader One of the coolest features of Reader is an AI reading assistant called *Ghostreader* (based on GPT-3). Ghostreader enables you to define terms, look up encyclopedia entries, simplify complex language, and much more, but one of its most powerful functions is asking a document a question. If you're on web, you can ask this FAQ your question using Ghostreader rather and likely find the answer you're looking for. Try it for yourself: Hit `Shift + G` to invoke Ghostreader at the document-level, select "Ask the document question", and input a specific question such as "How do I upload an OPML file?" or "Where do I find the Safari extension?" Nine times out of ten it should return what you're looking for! ([View Highlight](https://read.readwise.io/read/01gnb5qddaq90qyzqf41qkt6jh)) - Note: ? Based on the information provided, it does not appear that there is a limit on how many PDFs you can upload.