My friend and I have done a few buddy reads, but we read in different formats. I listen to audiobooks, and she reads print and ebooks. Because formats and editions can vary in length (for example, ebooks may include appendices or references not present in audiobooks), the percentage read between formats often doesn’t align. This leads to buddy read comments appearing out of sync.

I imagine that it's not realistic to perfectly align progress across all editions, so a possible workaround could be that organizers are given the option to require a 'reading context tag' (working title) before posting a comment. This tag could be freeform, such as "middle of chapter 2" or "right after <some non-spoiler event>," helping readers across formats judge whether a comment is safe to read. Organizers could also optionally allow participants to view tagged comments beyond their tracked progress.

Beyond mixed edition readers, this would also be especially helpful for buddy reads where some members have previously read the book. They might want to follow along with and react to a first-time reader’s thoughts as soon as they are posted.

I think that in either scenario (and probably some I did not think of), this type of feature could help maintain spoiler safety while making buddy reads more flexible.